Ensure the javelin is parallel to the ground. Look at the direction of your through. Approach runAfter you have the javelin in position, begin running towards your target with the javelinKeep your hips high and down on the balls of your feetLet your free arms swing across your bodyExtend the arm carrying the javelin fully behind you. Keep your head facing in the direction of your targetTurn so that the left side of your body faces your target. Cross over. Place yourright foot on the ground and your left foot forward and elevated. Put your right ahead in a lean back positionsPull the javelin back a little further so that the tip is lined up with your eyebrowsKeep the right foot close to the groundLet the right heel touch the groundAs the right foot moves forward, move the left foot up and lean your trunk back at 115 degree angle. Place your right foot on the ground and you left leg forward and elevatedDirect your shoulder and hips towards your left target. Wait for your left foot to touch the groundStraighten your torsoTurn your face toward the direction of the throw with the javelin parallel to your shoulderPosition your throwing and hand above shoulder level. ReleaseThrough the javelin with your arms as high as possiblePlant you left heels and thrust forward with your right footPull back with your left arm keeping it parallel to your right shoulderMove your throwing shoulder over your left legLift your left leg and move your throwing arm, with the elbow placed high and close to the midline. Release the javelin with your arm over your head in front of you. Follow throughLet your throwing arm travel diagonally across your body. For examples if you are throwing with your right arms, it should end up infront of your left side. Keep your left foot on the ground. Let the right leg pass the left foot and then stop you. Finish by standing on your right foot, with your left leg up behind you. Your right shoulder will turn left, with your chest facing to the left. PUPILS ACTIVITIESLearner to discuss various drills in javelin with the guidance of the teacherKLB TOP SCHOLAR PAG 47Creating and Performing in Creative Arts and Sports Composing MelodyMelodyActivity 1: Identifying Qualities of a Good MelodyThe melodies move in stepwise motion with a few leaps.


Finish by standing on your right foot, with your left leg up behind you. Your right shoulder will turn left, with your chest facing to the left. PUPILS ACTIVITIESLearner to discuss various drills in javelin with the guidance of the teacherKLB TOP SCHOLAR PAG 47Creating and Performing in Creative Arts and Sports Composing MelodyMelodyActivity 1: Identifying Qualities of a Good MelodyThe melodies move in stepwise motion with a few leaps. The melodies begin on notes d, m or s and end on d. They have a good melodic contour. They have several rhythmic patterns. Activity 2: Interpreting 4-bar Melodies in Simple TimeSing the melodies below and take note of the melodic contourTo interpret a melody, the following should be done:Identify the clef, key signature and time signature. Tap the rhythms of the melody. Write tonic sol-fas of the melody below the staff. Remember "doh' is the note that gives the key its name, for example, in C major, doh is C,Practise singing the tonic sol-fas of the melody, first in crotchets and then using the correct rhythm. Notice the movement of successive notes in each of the melodies. Stepwise motion is where the interval between any two neighbouring notes is not more than a step on the scale. In some cases there can be more than a step between two successive notes of a melody. This type of motion is called skipwise motion or movement by leaps. Each melody has a shape, which depends on the successive movement of notes. A melody can move upwards, downwards, in waves forming a curve and so on. This is referred to as the melodic shape or contour. Activity 3: Creating 1-bar Melodies in Simple Time on Treble ClefThings To RememberBefore you begin creating a melody, you should: draw the staff, add the treble clef, write the key signature of the scale you want to use, and write the time signature you will use. Work in PairsWhat are the qualities of a good melody as was discussed in the previous activity? Practise Writing a 4-bar melody in simple time in major scales of C, G, D and A. Sing or play the melody you have created. Describe the melodic motion and shape or contour.


Practise Writing a 4-bar melody in simple time in major scales of C, G, D and A. Sing or play the melody you have created. Describe the melodic motion and shape or contour. What is the first and the last note in each of the melodies? Activity 4: Playing or Singing Melodies Created by Self and OthersCan You Recall? What are the qualities of a good melody? Work in pairsTake turns to play each other's melodies. Discuss the qualities in each of the melodies played. Group Activity With the guidance of your teacher, use mobile apps or computer software to create, notate and play back 4-bar melodies. Activity 5: Appreciating Melodies Composed by Self and OthersListen and LearnYou have created 4-bar melodies in simple time in the major scales of C, G, D and AIn pairs, take turns to sing or play or use: digital devices to listen to and appraise each other's melodies. Take turns to sing your melodies to the class. Creating and Performing in Creative Arts and Sports HandballHandball Passes and reception in handballPassing is delivering the ball to a team mate during play in a handball game. Passing the ball helps in;Speeding up the gameCreating scoring chancesBreaking tight defenseReleasing pressure during playExpressing creative abilities during playQualities of a good passAccurate so that a player has no problem catching the ball. Fast and timely to exploit the play chance promptly. Useful a pass should be directed to that player whose position may disadvantage the opponent. Types of passesThere are three types of passes, namely;Jump passSide passFlick pass1. Jump passA jump pass is where a player leaps in to the air and throws the ball to a teammate before landing. It is completed at the peak of the jump with a player in control releasing the ball to the teammateStages of execution in jump pass a. PreparationTake off from the ground either on a single or double foot. Bring the passing arm high and back above the level of the headBring the non- passing arm slightly in front of your body Keep shoulders high and head up b. ExecutionAs you bring the passing arm forward to release the ball, pull the non-passing arm backwards at hip level.


PreparationTake off from the ground either on a single or double foot. Bring the passing arm high and back above the level of the headBring the non- passing arm slightly in front of your body Keep shoulders high and head up b. ExecutionAs you bring the passing arm forward to release the ball, pull the non-passing arm backwards at hip level. Release the ball to your teammate with a follow through and wrist action. 2. Side passA side pass is also known as wrist passes and is the most common way of passing the ball across the width of the court. This movement is called ball circulation. Stages of execution in side passa. PreparationStand with feet slightly closer together than shoulder-width apart from the target,the receiver should be on your right or left sideHold the ball on the passing hand with palm facing downIf the pass is to be made at the right side, hold the ball with the right hand , if the pass is to be made on the left side, hold the ball with the left handb. Executionswing the passing arm across the body from left to right when passing towards the right directionrelease the ball with full extension of the arm with a wrist actionstep sideways towards the direction of the pass for a follow- through3. Flick passA flick pass is an action made using the passing arm which quickly propels the ball forward. The release action of the ball is terminated with a forward wrist action. A. PreparationTake a staggered stance with the leg of the non- passing arm leading. Hold the ball with one hand in an open palm, fingers well spread behind it at shoulder levelThe non-passing arm should be extended outwards for balanceEyes should be focused on the target b. ExecutionStep with trailing foot forwardPush the ball forward towards the receiverRelease the ball by flexing the wrist and the fingers forward for a follow- through. This generates power to propel the ball and give it directions. ReceptionReception is the act of receiving the ball with one or both hands. The catch may vary from high level to medium or low level. Points for reception of the balla. PreparationStand on the balls of your feet shoulder-width apart facing the direction of the ball.


The catch may vary from high level to medium or low level. Points for reception of the balla. PreparationStand on the balls of your feet shoulder-width apart facing the direction of the ball. Extend your hands towards the ballMove forward to meet the oncoming ballKeep your arms pointed towards the ballYour hands should form a tunnel shape of a W formation ready to receive the ball. Preparation to catchb. TerminationOn contact with the ball, wrap the fingers around it and bend the elbows bring the ball towards the chest. Ensure the thumbs are behind the ball and get in to a ready position for your next action. Drills in hand ballsDrill 1: jump passingIn pairs, stand apart. Take three steps toward your partner and then take offPass the ball using a jump pass and walk back to your siting positionYour partner also takes three steps and then passes te ball back to you using a jump pass. Drill 2. Flick passIn groups of four, stand in a square formation, ass the ball around the square using flick. Drill 3: two line drillPlayer to form two linesThe leaders pass the ball using a flick passAfter making the pass, the leader joins the line from behindEnsure everyone get a chance to pass the ballSide pass drillsDrill 1: side passingIn pairs, stand 3m apart side by side. Pass the ball to one another using a wrist passDrill 2: pass curveIn groups of four, stand three meters apart in a semi-circleThe player with the ball to be at the extreme endPass the ball from right to left without skipping any playerWhen the ball reaches the end, pass the ball back to the leftDrill 3: down court drillIn pairs, stand 3 m apart facing the goal, walk down the court passing the ball using the side pass. Change the pace to a jog and continue passing the ball each other up and down the courtPupils activity Pg. 22Footwork in handball Principles of good landingLanding on the balls of the feetKnees should be slightly bent to cushion the shock on the impact of landingThis is also referred to as knee- deep landing. Stepping progression skills in handballDrill 1: individually jump, catch a ball and land on one foot.


Change the pace to a jog and continue passing the ball each other up and down the courtPupils activity Pg. 22Footwork in handball Principles of good landingLanding on the balls of the feetKnees should be slightly bent to cushion the shock on the impact of landingThis is also referred to as knee- deep landing. Stepping progression skills in handballDrill 1: individually jump, catch a ball and land on one foot. Drill 2: in pairs, stand 3m apart facing each other, jump, and catch a ball and land on both feetDrill 3: a the players are in circular formation passing and catching the ballb Catch the ball from a side pass land on both feet and take three steps and then pass it to the next player using a side pass. Drill 4: a the players are in a triangular formation passing and catching the ballb Catch the ball from a flick pass and land on both feet, take three steps andthen pass the ball using a flick pass. Drill 5:a in a group six form a line formationb Practice catching the ball and landing on both feet. Use a jump pass while passing. Dodging and marking in handball DodgingWhen dodging, a player may use body actions that mislead the defending player. It enables the attacking player to go past the defender and score goals with ease. MarkingMarking is a defensive action that limits the chances of attacking players gaining possession of the ball. Qualities of a good playerObservant the marking player needs to pay attention to the attackers who are likely to gain possession of the ball and drive forwardGood positioning ability to position himself or herself appropriately between the attacking player and their defending goalQuick time reaction this helps the marking player respond to unexpected tactical actions by the attacking players. Resilience and persistence the marking player should never give up on playing a defensive role. Communication good marking is a product of communicating with teammates to develop a suitable plan or approach to counter the playing actions of the attacking teamsCourageous a good marker should be courageous to withstand non-avoidable contacts that may occur during one on one tackling situationsPeripheral vision a player who is marking needs to see what is happening around him or her and not just focuses on the player being marked alone.


Qualities of a good playerObservant the marking player needs to pay attention to the attackers who are likely to gain possession of the ball and drive forwardGood positioning ability to position himself or herself appropriately between the attacking player and their defending goalQuick time reaction this helps the marking player respond to unexpected tactical actions by the attacking players. Resilience and persistence the marking player should never give up on playing a defensive role. Communication good marking is a product of communicating with teammates to develop a suitable plan or approach to counter the playing actions of the attacking teamsCourageous a good marker should be courageous to withstand non-avoidable contacts that may occur during one on one tackling situationsPeripheral vision a player who is marking needs to see what is happening around him or her and not just focuses on the player being marked alone. Body feign in handballBody feigns are performed by using the trunk legs. They involve a shift of balance and weight. This can be done with or without the ball. Body feigns are used to free the player from an opponent and get a better position for receiving or passing the ball. Types of dodging technics include:Single feign dodgeDouble feign dodgeSingle feign dodgeIn group of five players, form two lines facing one another 5m apartPlayers approach each otherIn closing to one another, each of them performs a single feign to the opposite side. Leaning point for double feign dodgeTake a position at least 5m in front of an opponentMake a short run and break it with a double foot landing referred to as a zero step Lean towards either the right or left and repeat the feigning. Complete the original intended love. Drill 1: Pair feign dodgeIn pairs without the ball, stand facing each otherOne of you to practice the double feign dodgeRepeat three times and switch rolesDrill 2: Quinque drillIn groups of five, place a cone in the court and make a line facing the coneSprint to the cone and stop on zero steps, feign to the right, then left and then move to the right to receive the ball. Dribbling in handballDribbling it is a technique in handball where the player bounces the ball on the ground once or repeatedly.


Complete the original intended love. Drill 1: Pair feign dodgeIn pairs without the ball, stand facing each otherOne of you to practice the double feign dodgeRepeat three times and switch rolesDrill 2: Quinque drillIn groups of five, place a cone in the court and make a line facing the coneSprint to the cone and stop on zero steps, feign to the right, then left and then move to the right to receive the ball. Dribbling in handballDribbling it is a technique in handball where the player bounces the ball on the ground once or repeatedly. Types of handball dribblingHigh dribbleLow dribbleDemonstrating low dribbleStand with the feet shoulder-width apartThe knees should be slightly bent and body weight on the balls of the feetPush the ball downwards using the wrist and the fingers for better controlThe arm of the non- dribbling hand should be extended outwards from the body for balanceUse a pump like action to bounce the ball repeatedly with the enough force so that it bounces slightly above knee level. This constitutes a low level. Control the ball by flexing the wrist and the fingersBounce the ball below knee level for a low dribbleKeep the head up and avoid looking at the ballLearning points for high dribbleStand with the feet shoulder- width apartKeep erect with a slight lean forward and body weight on the balls of the feetPush the ball downwards using the wrist and the fingers for better controlThe arm of the non-dribbling hand should be extended outwards from the body for balanceUse a pump like action to bounce the ball repeatedly with enough force so that it bounces slightly above knee level for a high. This constitutes a high dribble. Keep the head up and avoid looking at the ball. Drills of dribbling in handballDrill 1: Step and dribbleTake three steps, make one dribble and take three more steps.


This constitutes a high dribble. Keep the head up and avoid looking at the ball. Drills of dribbling in handballDrill 1: Step and dribbleTake three steps, make one dribble and take three more steps. Increase the number of dribbles between three- step sectionsAt the end of the sequence, make a shot or a passDrill 2: Walking drillWalk across the court with a ball five times making a high dribbleRepeat the drill using a low dribbleDrill 3: The cone drillPlace seven cones in a line 1.5m apartIn groups of five, practice zigzag movement pattern in and out of the cones one at a timeStart with a low dribble and later a high dribbleAs you perfect the dribble, make more challenging by shortening the distance between the conesDrill 4:The court drill Individually dribble a ball along a court marking using high and low dribbles. Use a movement pattern of three high dribble and three low dribbles. SHOOTING IN HANDBALLShooting it involves throwing the ball in to the opponent s goal to make a score. Safety measures to be observed when performing shooting in handballNever aim to hit or injure the goalkeeper with the ball. Take turn and shoot one player at a timeWarm up adequately before starting the shooting activityAdhere to the instructions given by the instructorBe conscious of the nature of the floor or the ground while making a falling or a dive shot. . Types of shots in handball include:Jump shotDive shotRunning shotFalling shotLob shotDemonstrating jump shotA jump shot is where a player can shoot from a stationary position and gain horizontal distance and the releasing powerfully towards the goal at the highest point of the jump. Make a shot run with a maximum of three steps while gripping the ballMake a single foot take off in the last step for an upward thrust. Bend the other leg at the knee for more force upward. Demonstration for a running shortRunning shot is executed while the player is in motion making the three steps progression.


Make a shot run with a maximum of three steps while gripping the ballMake a single foot take off in the last step for an upward thrust. Bend the other leg at the knee for more force upward. Demonstration for a running shortRunning shot is executed while the player is in motion making the three steps progression. Make two or three steps towards the attacking goal end then make a shot at the goalFollow through with a swing of the throwing handDemonstrating a dive shotTake a position outside the 6m line facing the attacking goal. Take off with both feet high and the head fast towards the goal area. Release the ball while airborne and land in the goal area with the body low. Convert your landing into a roll for safety. Learning points for falling shotTake a position outside the 6m line facing the goal. With the feet firm on the floor outside the goal area, fall towards the goal area . Release the ball before contacting the goal area with the hands or any other part of the .bodyLearning points for lob shotTake a position outside the 6m lineFace the goalkeeper who may have moved closer to you in defense Throw the ball in a curved path over the goalkeeper Flick the wrist to give the ball direction and accuracy.


Learning points for falling shotTake a position outside the 6m line facing the goal. With the feet firm on the floor outside the goal area, fall towards the goal area . Release the ball before contacting the goal area with the hands or any other part of the .bodyLearning points for lob shotTake a position outside the 6m lineFace the goalkeeper who may have moved closer to you in defense Throw the ball in a curved path over the goalkeeper Flick the wrist to give the ball direction and accuracy. Drills for shooting in handballDrill 1: Step and shootIn groups of five make a line facing the goal with the leader at the free throw lineThe leader makes a pass to the first player in the lineThe player makes 3 steps and then a jump shotAfter making a jump shot the player joins the line from the backRepeat the activity3 times then change to practice a running shotDrill 2: Drill and shootIn a group of four players, make a line at the substitution zone facing the goal where you intend to shootUse a high dribble to move towards the goal areaOn reaching the free throw line, catch the ball and make a jump shotRetrieve the ball and run along the goal line to the corner and then along the sideline to join your teammatesAfter three attempts change and practice a running shotDrill 3: Corner drillIn a group of five, make a line at the corner of the courtThe leader to stand at a point within the courtThe first player in the line to run along the goal area lineWhen at a comfortable position, catch the ball from the group leader and make a dive short. Pupils activities Pg. 35. CREATING AND PERFORMING IN CREATIVE ARTS AND SPORTS WESTERN SOLO INSTRUMENTWestern Solo InstrumentsActivity 1: Tuning the Descant Recorder or Any Other Solo Western Instrument Study the following instruments and answer the questions that follow. What can you see? With the guidance of your teacher and resource persons, watch a live or recorded solo instrumental performance. In groups, discuss the importance of tuning a solo Western instrument in preparation for a performance. Watch videos demonstrating techniques of tuning various Western instruments and apply them to your chosen instrument.


With the guidance of your teacher and resource persons, watch a live or recorded solo instrumental performance. In groups, discuss the importance of tuning a solo Western instrument in preparation for a performance. Watch videos demonstrating techniques of tuning various Western instruments and apply them to your chosen instrument. Activity 2: Playing the Scale Of C Major On StaffWhat I need to knowWestern instruments have different fingering charts to guide in playing of different pitches. Use digital devices to download the fingering charts for the instrument of choice. Below is the fingering chart for the Descant Recorder showing the notes of the scale of C major. Descant Recorder Fingering ChartIndividual ActivityPractise playing the notes of the scale of C major ascending and descending on your instrument using the fingering chart. On a digital device, watch videos to learn how to play the scale of C major. Use the fingering provided to the play the notes C D EF G A B C' on the descant recorder. Practise playing the scale in ascending and descending order. Group Activity Play familiar tunes in the scale of C major on your instrument. Activity 3: Sight Reading Simple Melodies in C Major To do individually and in groups. Look at the clef below. Check the key signature and keep the key in your head while playingLook at the time signature. Clap or tap the rhythms of each of the melodies before you play them. Locate the notes on the instrument. Look at the melodies and play. Sight-reading is playing of music without prior preparation. Your teacher will provide 2-bar melodies for you to sight-read. Do so without referring to the fingering chart or tapping the rhythms before playing. Activity 4: Playing with Appropriate TechniquesEvery instrument has specific techniques to be applied while playing. For example, for strings there is bowing, plucking, strumming, fingering; and for wind, there is tonguing, blowing and fingering. All the techniques when well applied ensure good tone quality. How To Produce a Good Tone on The Descant RecorderBlow gently into the descant recorder as you make the sound du with the tongue. This is referred to as tonguing and it helps to produce a clear sound. Do not blow too hard into the recorder because it will make a high pitch sound. If you are having trouble producing a sound after lots of practice, clean your recorder. Cover the air hole below the mouthpiece and blow in hard.


Do not blow too hard into the recorder because it will make a high pitch sound. If you are having trouble producing a sound after lots of practice, clean your recorder. Cover the air hole below the mouthpiece and blow in hard. Activity 5: Observing Performance DirectionsWhat I Need to KnowPerformance directions are words, phrases or signs showing the appropriate tempo, dynamics, articulation and repeats in a piece of music. The directions help to enhance the overall effect in a performance. With your teacher s guidance, play various melodies observing the performance directions shown. Your teacher will also help you search for short duets in C major to be played in pairs and groups. Creating and Performing in Creative Arts and SportsFootball.


INTEGRATED SCIENCEGRADE 7CBC JUNIOR SECONDARYSTRAND ONESCIENTIFIC INVESTIGATIONNOTE: Integrated science is taught through inquiry-based learning approaches with an emphasis on the 5Es: engagement, exploration, explanation, elaboration and evaluation. Integrated Science: What is integrated science? Integrated Science is an interdisciplinary approach to science education that seeks to connect and integrate concepts and ideas from different branches of science, such as biology, chemistry, physics, and earth science. Components of Integrated scienceThe components of Integrated Science may vary depending on the curriculum and educational approach, but typically include:Basic scientific concepts: students learn about fundamental scientific principles and theories, such as the nature of matter and energy, the structure of the universe, and the process of evolution. Laboratory experiences: hands-on experiments and investigations provide students with opportunities to apply scientific concepts and methodologies. Problem solving and inquiry: students learn to use scientific reasoning and inquiry to design experiments, analyze data, and make informed conclusions. Scientific literacy: students learn to critically evaluate scientific information, understand the impact of science and technology on society, and appreciate the ethical considerations involved in scientific research. Integration of scientific concepts: the curriculum emphasizes connections between different branches of science and the interplay between science, technology, and society. Pathways related to integrated ScienceThe provision of pathways at senior school is based on the aspiration that all learners can be successful in life. These pathways are contained in one-word STEM Science, Technology, Engineering and Mathematics Subjects in the STEM pathway includePure ScienceStudents in this track shall be expected to join a university or other middle level college to pursue careers in area such as education, medicine, pharmacy, science BSc , industrial science and actuarial science. Some will be able to join the world of work under experienced persons and later undergo further training and apprenticeships to advance their skills. Applied SciencesThe Applied science track provides a specialization opportunity for learners who have demonstrated the interest, abilities and aptitude to pursue a career in applied sciences. The track builds on the competencies acquired at lower secondary in the areas of mathematics and integrated science. It equips learners with the knowledge, skills and attitudes necessary for advanced careers in applied sciences offered in middle level colleges and universitiesStudents graduating from this track shall be expected to join middle level colleges or universities to pursue careers in areas such as agricultural engineering, computer engineering, foods science and technology, business and hospitality and home economics.


Applied SciencesThe Applied science track provides a specialization opportunity for learners who have demonstrated the interest, abilities and aptitude to pursue a career in applied sciences. The track builds on the competencies acquired at lower secondary in the areas of mathematics and integrated science. It equips learners with the knowledge, skills and attitudes necessary for advanced careers in applied sciences offered in middle level colleges and universitiesStudents graduating from this track shall be expected to join middle level colleges or universities to pursue careers in areas such as agricultural engineering, computer engineering, foods science and technology, business and hospitality and home economics. They shall also be able to join the world of work where they shall work under the guidance of a specialist as they advance their skills on the job, through apprenticeships or further training. The pure and applied sciences curriculum shall prepare learners to graduate with a senior school national certificate that will open the following career opportunities for them:Enroll directly into a university for a degree in science related subjects. Enroll into middle level colleges for a diploma in science related fields. Join the world of work to work under skilled personnelTechnical and EngineeringThe schools shall prepare learners with foundational skills in applied sciences and moderntechnology. Emphasis shall be on the understanding and practical application of basic principles of science and mathematics in various fields such as engineering, design, agriculture, business, computers and data processing, environmental and resource management and health. Career opportunities related to Integrated ScienceEnvironmental managerForensic laboratory technicianHealth education specialistLaboratory technicianPublic health advisor analystResearch assistantScientific journalistSoftware DeveloperDentistDoctorForensic scientistGeneticistLawyerMarine biologistNeuroscientistNurseNutritionistOptometristPharmacistPhysiotherapistPsychiatristUrban plannerTeacher ProfessorVeterinarianVirologistImportance of Integrated ScienceLearning in the 21st century should have context, be linked to community life, be student centered and be collaborative. Learning has context mean that the content of learning material must be associated with the real world. In this way, the material discussed in the school is close to the daily life of the students. In learning process, students more involved actively to construct their competences. Construction of competencies in learning is done collaboratively. Hence, these four principles of learning are the essence of the 21st century learning.


In learning process, students more involved actively to construct their competences. Construction of competencies in learning is done collaboratively. Hence, these four principles of learning are the essence of the 21st century learning. Integrated science learning is a good way to apply the essence of learning in the 21st century. In integrated science learning students are encouraged to connect the learning materials content to real-world contexts. Students are involved actively in exploring the real-world contexts which relevant to the learning material, conducting the collaborative investigation, and communicating the results of the investigation. Thus, the learning can be implemented holistically, authentically, meaningfully and actively. Aims to improve students understanding on the environmentImportance of Scientific KnowledgeAnd that knowledge is useful for all sorts of things:designing bridges,slowing climate change, andprompting frequent hand washing during flu season. Scientific knowledge allows us to develop new technologies,solve practical problems, andmake informed decisions both individually and collectively. Laboratory safetyA place equipped for experimental study in a science or for testing and analysis. A research laboratory. Broadly: a place providing opportunity for experimentation, observation, or practice in a field of study. Common hazards and their symbolsHazard pictograms alert us to the presence of a hazardous chemical. The pictograms help us to know that the chemicals we are using might cause harm to people or the environment. Here are a few of them. Biohazard It provides warning on lab equipment that may contain biohazardous materials like blood samples. Causes of accidents in the laboratory1. CHEMICALSIf you handle chemicals, you need to wear protective gloves. Treat chemicals with the necessary caution, measure chemicals carefully, contain potentially irritating or hazardous chemicals and use only approved containers when you re transferring chemicals. Chemical burns should be treated by flushing the affected area with a large amount of cool, running water for at least 15 minutes. If the burn area is large or if the affected person is dizzy or weak, call 911. If you work in a chemistry lab, ensure you are taking the proper steps to be safe around the chemicals in your workplace. 2. HEATExercise caution when handling hot items. Hastily or improperly handling these items without the correct tools can cause serious burns. Workers should be properly using water baths, tongs and cooling equipment. Be careful not to touch hot surfaces with your bare hand.


Hastily or improperly handling these items without the correct tools can cause serious burns. Workers should be properly using water baths, tongs and cooling equipment. Be careful not to touch hot surfaces with your bare hand. If you suffer a heat burn in the lab, run the burned area under cool water for five minutes. 3. CUTS AND SCRAPESUsing sharp tools in the laboratory setting can cause scrapes and cuts. Workers may also use sharp objects, such as needles and razor blades, or need to clean up broken glass. To avoid cutting yourself on these items, carefully wrap them so that you can safely carry and dispose of them. 4. CONTAMINATIONAvoiding contamination is key to ensuring safety in the lab setting. Though the advice to wash your hands may seem quite basic, it s an important procedure to avoid contamination. After you interact with any foreign substance, you should wash your hands thoroughly. Protect your skin and clothing with the proper equipment, such as gloves, glasses and a lab coat. You can contaminate areas outside of the lab if you carry bacteria or other substances on your clothing or skin, which can cause the spread of illnesses and other dangers. 5. Inhaling SubstancesAnother common type of lab accident is inhalation. If you inhale chemicals or gases in a space that isn t properly ventilated, you may experience nausea, headaches or fainting. Ensure you follow proper procedures for ventilation, such as using ventilation fans and measuring the amount of gas emitted in a room. 6. FIRESWhen working with hot surfaces and flammable materials, fires become a common danger. Review and practice the proper procedures to ensure you minimize the risk of fire in the laboratory. All flammable materials should be properly stored and sealed. Inspect burners for leaks to avoid sudden flares. 7. SPILLS AND BREAKSIn the lab, glass beakers may be dropped and break. Liquids may be spilled. Generally, these accidents are caused by rushing, being negligent and not properly following procedures. While you work, move carefully through every step. Moving slowly but more steadily will be much better for the safety of yourself and your colleagues. Though students have a responsibility to themselves and their colleagues to exercise proper safety measures and follow protocol, the laboratory environment itself should also follow guidelines from the Occupational Safety and Health Administration OSHA to provide workers with safe working conditions.


While you work, move carefully through every step. Moving slowly but more steadily will be much better for the safety of yourself and your colleagues. Though students have a responsibility to themselves and their colleagues to exercise proper safety measures and follow protocol, the laboratory environment itself should also follow guidelines from the Occupational Safety and Health Administration OSHA to provide workers with safe working conditions. Lack of warning labels and signsInadequate eye and face protection against chemical and environmental hazardsLack of protection against hazardous sources of energy, such as electric powerInadequate respiratory protection for working with gases, chemicals and smokeFirst Aid safety measures for common laboratory accidentsGeneral course of actionRELOCATE everyone in the immediate work area to a safe location. ALERT-CONFINE- If it can be done safely, close doors to confine the area where the emergency occurred. Post an Emergency Hangtag on the door s to prevent reentry by other personnel. EVACUATE the building through the nearest exit. Do not run. Do not use elevators. REPORT to your designated meeting site. REENTER once the lab has been cleared by emergency personnel. First Aid: Eye Exposure to Hazardous ChemicalForcibly hold both eyes open under an emergency eyewash to ensure an effective wash behind both eyelids. If contact lenses are being worn, remove the contacts while flushing. Continue flushing the eyes underneath the eyewash until emergency personnel arrive. Report the injury to your principal investigator and or laboratory facility manager. First Aid: Skin ExposureWash affected area s with tepid water from an emergency safety shower. Take care not to break skin. Remove or cut off contaminated clothing while rinsing. Do not pull contaminated clothing over the head. For chemical and thermal burns, flush affected area s with water from the safety shower, if indicated in safety data sheet. For blood, biological, or radiological exposures use soap and water. Keep flushing affected area s underneath the safety shower until emergency personnel arrive. Report the injury to your principal investigator and or laboratory facility manager. First Aid: Inhalation of Chemical Vapors, Fumes or SmokeIf exposed individual is unconscious, do NOT enter the lab if a possibility of oxygen depletion, toxic vapors, or an explosive atmosphere exists. If exposed individual is conscious, move the person to fresh, uncontaminated air. Report the injury to your principal investigator and or laboratory facility manager.


First Aid: Inhalation of Chemical Vapors, Fumes or SmokeIf exposed individual is unconscious, do NOT enter the lab if a possibility of oxygen depletion, toxic vapors, or an explosive atmosphere exists. If exposed individual is conscious, move the person to fresh, uncontaminated air. Report the injury to your principal investigator and or laboratory facility manager. First Aid: Chemical IngestionIf safe to do so, move affected individual to an uncontaminated area. Do not induce vomiting or drink water or other liquids unless instructed to do so by emergency personnel. Report the injury to your principal investigator and or laboratory facility manager. Importance of safety in the laboratoryLaboratory safety is an essential part of ensuring the health and safety of workers and researchers in laboratory settings. Laboratories can be hazardous environments with various potential risks, including chemical spills, fires, explosions, and exposure to hazardous substances. Lab safety is important because it can prevent injury, keep us from making mistakes and save lives. Lab safety equipment can prevent injury. Lab safety equipment can help you avoid making mistakes. Lab safety equipment can save lives. Safety is important when working in the lab because it helps you avoid injury, keep yourself from making mistakes and save lives of others who may be nearby when an accident happens, or if there is a fire or other emergency situation that needs to be handled quickly and safely by someone who knows what they're doing before the situation gets out of hand. Following lab safety rules is part of being a good citizen. Following lab safety rules is part of being a good citizen. When you follow lab safety rules, you are doing your part to keep everyone safe. You are protecting yourself, your peers and coworkers, and everyone around you. Lab safety rules help prevent accidents and injuries, which means they can also save lives. We should follow the lab safety protocols to stay safe and healthy! By following the lab safety protocols, you will stay safe and healthy. It is absolutely critical that you follow all the rules of your lab protocol when conducting experiments in the lab. This allows you to avoid accidents and contamination, which can cause injury or illness. You should always wear protective clothing goggles, gloves and a face mask to keep yourself safe from hazardous materials such as chemicals or glass shards if an accident occurs in the laboratory. You should never eat or drink anything in the laboratory because it could easily contaminate your food with chemicals or bacteria potentially harmful for consumption by humans!


This allows you to avoid accidents and contamination, which can cause injury or illness. You should always wear protective clothing goggles, gloves and a face mask to keep yourself safe from hazardous materials such as chemicals or glass shards if an accident occurs in the laboratory. You should never eat or drink anything in the laboratory because it could easily contaminate your food with chemicals or bacteria potentially harmful for consumption by humans! Basic Science SkillsBasic skills in science1. ObservingThis is the most basic skill in science. Observations are made by using the 5 senses. Good observations are essential in learning the other science process skills. Examples:The learner will be blind folded and make observations using the sense of touch. The learner will create observations about a coin using the 5 senses. The learner will mix primary colors to create more colors. 2. CommunicatingIt is important to be able to share our experiences. This can be done with graphs, diagrams, maps, and spoken word. Examples:The learner will create a line graph showing the relationship between speed and the mass of a marble. The learner will discuss possible errors with other classmates. 3. ClassifyingAfter making observations it is important to notice similarities, differences, and group objects according to a purpose. It is important to create order to help comprehend the number of objects, events, and living things in the world. Examples:The learner will use a magnet to classify objects as magnetic or nonmagnetic. The learner will use a balance and sort objects according to mass. The learner will combine different liquids with water to determine which is more or less dense. 4. InferringAn inference is an explanation based on an observation. It is a link between what is observed and what is already known. Examples:The learner will write a conclusion at the end of each investigation. The learner will create inferences about observations they made about a mystery object. I infer it is solid rather than hollow. 5. MeasuringMeasuring is important in collecting, comparing, and interpreting data. It helps us classify and communicate with others. The metric system should be used to help understand the scientific world. Examples:The learner will find the mass of different liquids that have the same volume. The learner will use technology to find the speed of a toy truck. The learner will measure the distance a marble travels. 6. PredictingWhat do you think will happen? It is an educated guess based on good observations and inferences about an observed event or prior knowledge.


6. PredictingWhat do you think will happen? It is an educated guess based on good observations and inferences about an observed event or prior knowledge. Examples:The learner will predict what is a box based on observations using the sense of touch. The learner will write a hypothesis about the effect of increasing the salt on the buoyancy of an egg. 7. Manipulative skillIn science, manipulative skills emphasize the use and handling of scientific apparatus and chemical substances during scientific investigation in the laboratory. Importance of reading packing labels on products quantitiesIt helps in knowing the quantity of the productIt helps in knowing the product specifications like:Conditions for storageDate of expiryHow to use the productPossible side effectsWhat to do in case of emergenciesHow to dispose the product among othersSI UnitsThe International System Of Units SI is the metric system that is used universally as a standard for measurements. SI units play a vital role in scientific and technological research and development. SI unit is an international system of measurements that are used universally in technical and scientific research to avoid the confusion with the units. Having a standard unit system is important because it helps the entire world to understand the measurements in one set of unit systems. Following is the table with base SI units:There are 7 SI base units. The seven units along with their SI unit and symbol are given below:Unit of length, meter m : Meter is the SI unit of length and is defined by taking the fixed value of the speed of light in vacuum. It is expressed as m.s-1. Unit of mass, kilogram kg : Kilogram is the SI unit of mass and is defined by taking the fixed value of the Planck constant. It is expressed as kgUnit of time, second s : Second is the SI unit of time and is defined by taking the fixed value of Cesium frequency. Unit of electric current, ampere A : Ampere is the SI unit of electric current and is defined by taking the fixed value of the elementary charge. Unit of thermodynamic temperature, Kelvin K : Kelvin is the SI unit of thermodynamic temperatureUnit of the amount of substance, mole mol : Mole is the SI unit of the amount of substance and is defined by the fixed value of Avogadro constant NA.


It is expressed as kgUnit of time, second s : Second is the SI unit of time and is defined by taking the fixed value of Cesium frequency. Unit of electric current, ampere A : Ampere is the SI unit of electric current and is defined by taking the fixed value of the elementary charge. Unit of thermodynamic temperature, Kelvin K : Kelvin is the SI unit of thermodynamic temperatureUnit of the amount of substance, mole mol : Mole is the SI unit of the amount of substance and is defined by the fixed value of Avogadro constant NA. Unit of luminous intensity, candela cd : Candela is the SI unit of luminous intensity and is defined by the fixed value of the luminous efficacy. Laboratory apparatusAn apparator apparatus are scientific tools equipment used in performing scientific experiments. The conventional apparator used in performing scientific experiments is called standard apparator apparatus. If the conventional standard apparator apparatus is not available, an improvised apparator apparatus may be used in performing scientific experiments. An improvised apparator apparatus is one used in performing a scientific experiment for a standard apparator apparatus. Most standard apparatus in a school chemistry laboratory are made of glass because: i Glass is transparent and thus reactions interactions inside are clearly visible from outside ii Glass is comparatively cheaper which reduces cost of equipping the school chemistry laboratory iii Glass is comparatively easy to clean wash after use. Iv Glass is comparatively unreactive to many chemicals. Apparatus are designed for the purpose they are intended in a school chemistry laboratory:Apparatus for measuring volume1. Measuring cylinderMeasuring cylinders are apparatus used to measure volume of liquid solutions. They are calibrated graduated to measure any volume required to the maximum. Measuring cylinders are named according to the maximum calibrated graduated volume e.g.


Measuring cylinderMeasuring cylinders are apparatus used to measure volume of liquid solutions. They are calibrated graduated to measure any volume required to the maximum. Measuring cylinders are named according to the maximum calibrated graduated volume e.g. 10ml measuring cylinder is can hold maximum calibrated graduated volume of 10mililitres 10 cubic centimetres 50ml measuring cylinder is can hold maximum calibrated graduated volume of 50mililitres 50 cubic centimetres 250ml measuring cylinder is can hold maximum calibrated graduated volume of 250mililitres 250 cubic centimetres 1000ml measuring cylinder is can hold maximum calibrated graduated volume of 1000mililitres 1000 cubic centimetres 2. BuretteBurette is a long and narrow thin apparatus used to measure small accurate and exact volumes of a liquid solution. It must be clamped first on a stand before being used. It has a tap to run out the required amount out. They are calibrated graduated to run out small volume required to the maximum 50ml 50cm3. The maximum 50ml 50cm3 calibration graduation reading is at the bottom .This ensure the amount run out from a tap below can be determined directly from burette reading before and after during volumetric analysis. Burettes are expensive and care should be taken when using them. 3. I PipettePipette is a long and narrow thin apparatus that widens at the middle used to measure and transfer small very accurate exact volumes of a liquid solution. It is open on either ends. The maximum 25ml 25cm3 calibration graduation mark is a visible ring on one thin end. To fill a pipette to this mark, the user must suck up a liquid solution upto a level above the mark then adjust to the mark using a finger. This requires practice. Ii Pipette fillerPipette filler is used to suck in a liquid solution into a pipette instead of using the mouth. It has a suck, adjust and eject button for ensuring the exact volume is attained. This requires practice. 4. Volumetric flask. A volumetric flask is thin narrow but widens at the base bottom. It is used to measure very accurate exact volumes of a liquid solution. The maximum calibration graduation mark is a visible ring.


A volumetric flask is thin narrow but widens at the base bottom. It is used to measure very accurate exact volumes of a liquid solution. The maximum calibration graduation mark is a visible ring. Volumetric flasks are named according to the maximum calibrated graduated volume e.g. 250ml volumetric flask has a calibrated graduated mark at exact volume of 250mililitres 250centimetres 1l volumetric flask has a calibrated graduated mark at exact volume of one litre 1000 cubic centimeters 2l volumetric flask has a calibrated graduated mark at exact volume of two litres 2000 cubic centimeters 5. Dropper teat pipetteA dropper teat pipette is a long thin narrow glass rubber apparatus that has a flexible rubber head. A dropper teat pipette is used to measure very small amount drops of liquid solution by pressing the flexible rubber head. The numbers of drops needed are counted by pressing the rubber gently at a time b Apparatus for measuring mass1. Beam balanceA beam balance has a pan where a substance of unknown mass is placed. The scales on the opposite end are adjusted to balance with the mass of the unknown substance. The mass from a beam balance is in grams. 2. Electronic electric balance. An electronic electric balance has a pan where a substance of unknown mass is placed. The mass of the unknown substance in grams is available immediately on the screen. C Apparatus for measuring temperatureA thermometer has alcohol or mercury trapped in a bulb with a thin enclosed outlet for the alcohol mercury in the bulb. If temperature rises in the bulb, the alcohol mercury expand along the thin narrow enclosed outlet. The higher the temperature, the more the expansionOutside, a calibration graduation correspond to this expansion and thus changes in temperature. A thermometer therefore determines the temperature when the bulb is fully dipped in to the substance being tested. To determine the temperature of solid is thus very difficult. D Apparatus for measuring timeThe stop watch clock is the standard apparatus for measuring time. Time is measured using hours, minutes and second. Common school stop watch clock has start, stop and reset button for determining time for a chemical reaction. This requires practice. E Apparatus for scooping1.


The narrow mouth ensures no spillage. Conical flasks are named according to the maximum volume they can hold e.g. 250ml Conical flasks hold a maximum volume of 250mililitres 250 cubic centimeters 500ml Conical flasks hold a maximum volume of 500ml 1000 cubic centimeters 5. Round bottomed flaskA round bottomed flask is a moderately narrow glass apparatus with a wide round base and no calibration graduation. Round bottomed flask thus carry hold exact volumes of liquids that have been measured using other apparatus. The narrow thin mouth prevents spillage. The flask can also hold weighed solids. A round bottomed flask must be held clamped when in use because of its wide narrow base. 6. Flat bottomed flaskA flat bottomed flask is a moderately narrow glass apparatus with a wide round base with a small flat bottom. It has no calibration graduation. Flat bottomed flasks thus carry hold exact volumes of liquids that have been measured using other apparatus. The narrow thin mouth prevents spirage. They can also hold weighed solids. A flat bottomed flask must be held clamped when in use because it s flat narrow base is not stable. G Apparatus for holding unstable apparatus during heating . 1. Tripod standA tripod stand is a three legged metallic apparatus which unstable apparatus are placed on during heating .Beakers. Conical flasks, round bottomed flask and flat bottomed flasks are placed on top of tripod stand during heating . 2. Wire gauze meshWire gauze mesh is a metallic iron plate of wires crossings. It is placed on top of a tripod stand: i Ensure even distribution of heat to prevent cracking glass apparatus ii Hold smaller apparatus that cannot reach the edges of tripod stand3 Clamp standA clamp stand is a metallic apparatus which tightly hold apparatus at their neck firmly. A clamp stand has a wide metallic base that ensures maximum stability. The height and position of clamping is variable. This require practice4. Test tube holderA test tube holder is a hand held metallic apparatus which tightly hold test boiling ignition tube at their neck firmly on the other end. Some test tube holders have wooden handle that prevent heat conduction to the hand during heating. 5. Pair of tong.


Some test tube holders have wooden handle that prevent heat conduction to the hand during heating. 5. Pair of tong. A pair of tong is a scissor-like hand held metallic apparatus which tightly hold firmly a small solid sample on the other end. 6. Gas jarA gas jar is a long wide glass apparatus with a wide base. It is open on one end. It is used to collect put gases. This requires practice. H Apparatus for holding directing liquid solutions funnels to avoid spillage . 1. Filter funnelA filter funnel is a wide mouthed mainly plastic apparatus that narrow drastically at the bottom to a long extension. When the long extension is placed on top of another apparatus, a liquid solution can safely be directed through the wide mouth of the filter funnel into the apparatus without spirage. Filter funnel is also used to place a filter paper during filtration. 2. Thistle funnelA thistle funnel is a wide mouthed glass apparatus that narrow drastically at the bottom to a very long extension. The long extension is usually drilled through a stopper cork. A liquid solution can thus be directed into a stoppered container without spillage3. Dropping funnelA dropping funnel is a wide mouthed glass apparatus with a tap that narrow drastically at the bottom to a very long extension. The long extension is usually drilled through a stopper cork. A liquid solution can thus be directed into a stoppered container without spillage at the rate determined by adjusting the tap. 4. Separating funnelA separating funnel is a wide mouthed glass apparatus with a tap at the bottom narrow extension. A liquid solution can thus be directed into a separating funnel without spillage. It can also safely be removed from the funnel by opening the tap. It is used to separate two or more liquid solution mixtures that form layers immiscible. This requires practice. H Apparatus for heating Burners1. Candle, spirit burner, kerosene stove, charcoal burner jiko are some apparatus that can be used for heating. Any flammable fuel when put in a container and ignited can produce some heat. 2. Bunsen burnerThe Bunsen burner is the standard apparatus for heating in a Chemistry school laboratory. It was discovered by the German Scientist Robert Wilhelm Bunsen in1854. A Diagram of a Bunsen burnerA Bunsen burner uses butane laboratory gas as the fuel.


Bunsen burnerThe Bunsen burner is the standard apparatus for heating in a Chemistry school laboratory. It was discovered by the German Scientist Robert Wilhelm Bunsen in1854. A Diagram of a Bunsen burnerA Bunsen burner uses butane laboratory gas as the fuel. The butane laboratory gas is highly flammable and thus usually stored safely in a secure chamber outside Chemistry school laboratory. It is tapped and distributed into the laboratory through gas pipes. The gas pipes end at the gas tap on a chemistry laboratory bench .If opened the gas tap releases butane laboratory gas. Butane laboratory gas has a characteristic odor smell that alerts leakages open gas tap. The Bunsen burner is fixed to the gas tap using a strong rubber tube. The Bunsen burner is made up of the following parts: i Base plate to ensure the burner can stand on its own ii Jet-a hole through which laboratory gas enters the burner iii Collar sleeve-adjustable circular metal attached to the main chimney burell with a side hole entry. It controls the amount of air entering used during burning. Iv Air hole- a hole entry formed when the collar side hole is in line with chimney side hole. If the collar side hole is not in line with chimney side hole, the air hole is said to be closed If the collar side hole is in line with chimney side hole, the air hole is said to be open v Chimney- tall round metallic rod attached to the base plate. B Procedure for lighting igniting a Bunsen burner1. Adjust the collar to ensure the air holes are closed. 2. Connect the burner to the gas tap using a rubber tubing. Ensure the rubber tubing has no side leaks. 3. Turn on the gas tap. 4. Ignite the top of the chimney using a lighted match stick gas lighter wooden splint. 5. Do not delay excessively procedure iv from iii to prevent highly flammable laboratory gas from escaping leaking. Parts and functions of a microscopeA compound microscope is a high-power microscope that has higher magnification levels than a low-power or dissection microscope. It is used to examine tiny specimens like cell structures that cannot be viewed at lower magnification levels. A compound microscope is made up of both structural and optical components.


Parts and functions of a microscopeA compound microscope is a high-power microscope that has higher magnification levels than a low-power or dissection microscope. It is used to examine tiny specimens like cell structures that cannot be viewed at lower magnification levels. A compound microscope is made up of both structural and optical components. The 3 basic structural components are the head, arm and base. The body or head comprises the optical parts present in the upper part of the microscopeThe arm connects and supports the base and head of the microscope. Also, it is used to carry the microscope. Base of the microscope supports the microscope and comprises the illuminatorThe optical part of the microscope includes:EyepieceEye tubeObjective lensesNosepieceAdjustment knobsStageIlluminatorCondenser and condenser focus knobDiaphragmThe ocular or eyepiece is what an observer looks through and is present in the upper portion of the microscope. The eyepiece tube clasps the eyepieces which are positioned above the objective lens. The objective lenses are the main optical lenses. They range in various magnifications from 4x to 100x and generally include 3 to 5 lenses on a single microscope. Nosepiece houses the objective lenses. The fine and coarse focus knobs are the adjustment knobs that are often used to focus the microscope. They are coaxial knobs. This means the focusing system of both fine and coarse focus are mounted on the same axis. There is also a condenser focus knob which moves the condenser up or down to control the lightingThe stage is where the specimen to be viewed is placed. A mechanical stage is often used when working on a specimen at a higher magnification. This is when delicate movement of the specimen is required. Stage clips are operated to hold the slide in place. To see different areas of the specimen, the observer must physically move the slide. A separate knob is present to move the slide in the mechanical stage. The aperture is a tiny hole in the stage via which the transmitted light enters the stage. An illuminator acts as the light source and is typically located at the microscope s base. Most light microscopes operate on halogen bulbs with low voltage and also have variable and continuous lighting control within the base. A condenser is typically used to gather and focus the illuminator s light onto the specimen. It is found beneath the stage and is often observed in conjunction with a diaphragm or iris.


Most light microscopes operate on halogen bulbs with low voltage and also have variable and continuous lighting control within the base. A condenser is typically used to gather and focus the illuminator s light onto the specimen. It is found beneath the stage and is often observed in conjunction with a diaphragm or iris. Iris or Diaphragm regulates the amount of light that reaches the specimen. It is situated above the condenser but beneath the stage. Functions of MicroscopeThe primary function of a microscope is to study biological specimens. A microscope solely functions on two concepts magnification and resolution. Magnification is simply the ability of the microscope to enlarge the image. Whereas the ability to analyse minute details depends on the resolution. Compound and dissection microscopes are the two types of microscopes that are mostly used in schools for educational purposes. Functions of compound microscopeIt simplifies the study of viruses and bacteria. They are used in pathology labs to make an easy diagnosis of diseases. They are also used in forensic laboratories to identify human fingerprints. Common school laboratory safety rulesThe following safety guideline rules should be followed by chemistry laboratory users: i Enter the laboratory with permission in an orderly manner without rushing pushing scrabbling. Ii Do not try unauthorized experiments. They may produce flammable, explosive or toxic substances that affect your health. Iii Do not taste any chemical in the laboratory. They may be poisonous. Iv Waft gas fumes to your nose with your palm. Do not inhale smell gases directly. They may be highly poisonous toxic. V Boil substances with mouth of the test tube facing away from others and yourself. Boiling liquids spurt out portions of the hot liquid. Products of heating solids may be a highly poisonous toxic gas. Vi Wash with lots of water any skin contact with chemicals immediately. Report immediately to teacher laboratory technician any irritation, cut, burn, bruise or feelings arising from laboratory work. Vii Read and follow safety instruction. All experiments that evolve produce poisonous gases should be done in the open or in a fume chamber. Viii Clean your laboratory work station after use. Wash your hand before leaving the chemistry laboratory. Ix In case of fire, remain calm, switch of the source of fuel-gas tap. Leave the laboratory through the emergency door. Use fire extinguishers near the chemistry laboratory to put of medium fires. Leave strong fires wholly to professional fire fighters.


Leave the laboratory through the emergency door. Use fire extinguishers near the chemistry laboratory to put of medium fires. Leave strong fires wholly to professional fire fighters. X Do not carry unauthorized item from a laboratory. MIXTURES, ELEMENTS AND COMPOUNDSMixturesA mixture is a combination of two or more pure substances which can be separated by physical means. There are two types of mixtures:General Properties of MixturesMixtures are made up of two or more substances that are not chemically combined with each other. The properties of mixtures are listed below. The components of a mixture each keep their original properties. The separation of components can be easily done. The proportion of the components is variable. Examples of MixturesCrude oil: A mixture of organic compounds mainly hydrocarbons Seawater: A mixture of various salt and water. Air: a mixture of various gases like oxygen, carbon dioxide, nitrogen, argon, neon, etc. Ink: A mixture of coloured dyes. Gunpowder: A mixture of sulfur, potassium nitrate and carbon. There are two main types of mixtures: homogeneous mixtures and heterogeneous mixtures. The types of mixtures are discussed below. Heterogeneous MixtureWhat is a Heterogeneous Mixture? A mixture of sand mixed with salt is an example of a heterogeneous mixture. Heterogeneous mixtures possess different properties and compositions in various parts i.e. the properties are not uniform throughout the mixture. Examples of Heterogeneous mixtures air, oil, water, etc. Homogeneous MixtureWhat is a Homogeneous Mixture? Sugar mixed with water is the most common example of a homogeneous mixture. Homogeneous mixtures can be defined as the mixtures which possess the same properties and combination throughout their mass. Examples of Homogeneous mixtures alloys, salt, and water, alcohol in water, Cup of Coffee, Mouthwash, DetergentPure And Impure Substancesa substance is said to be pure if it is made up of only one kind of molecule or particle. Pure substances normally cannot be separated by simple physical methods and are largely classified as elements and compounds. Substances are either pure or impure. A pure substance is one which contains only one substance. An impure substance is one which contains two or more substances. A pure substance is made up of a pure solid, pure liquid or pure gas.


A pure substance is one which contains only one substance. An impure substance is one which contains two or more substances. A pure substance is made up of a pure solid, pure liquid or pure gas. Characteristics of Pure SubstanceThey are perfectly homogenous in nature. They are made up of only one kind of atoms or molecules. They have a fixed composition. It has fixed density, melting point and boiling point etc. Characteristics of Impure SubstanceIt does not have any specific properties; the properties of the mixture are a result of the average properties of all the constituents. It is formed as a result of a physical change. They have a variable composition. The mixtures are either heterogeneous or homogenous mixture in nature. Melting Point and boiling PointThe melting point is usually defined as the point at which materials changes from a solid to a liquid. The boiling point of a liquid is the temperature at which the vapour pressure of the liquid becomes equal to the atmospheric pressure of the liquid s environment. At this temperature, the liquid is converted into a vapour. The boiling point of the liquid depends upon the pressure of the surrounding. When the liquid is at high pressure, it has a higher boiling point than the boiling point at normal atmospheric pressure. The boiling point of different liquids is different for a given pressureThe boiling point for any material is the temperature point at which the material transforms into the gas phase in the liquid phase. This happens at 100 degrees centigrade for water. The Celsius scale was in fact created on the basis of the ice water melting point and the liquid water vapor boiling point. Each substance carries its own boiling point. The boiling point of a substance is dependent on the pressure of its surroundings. In mountainous terrains where the altitude is high , the pressure of the atmosphere is relatively lower than the atmospheric pressure at sea level. This is the reason why food cooks at a slower pace in mountainous areas the lower atmospheric pressure causes water to boil at temperatures below 100oC . When all the particles in the liquid phase have been transformed into the gas phase, the temperature begins to rise again, as long as heat is still being applied to the surrounding system. As the temperature starts to increase, so does the particle s kinetic energy. Boiling Point of WaterWater can boil, raise temperature or decrease air pressure, in two ways. At sea level, it is the pressure of air that causes water to boil at 100oC.


As the temperature starts to increase, so does the particle s kinetic energy. Boiling Point of WaterWater can boil, raise temperature or decrease air pressure, in two ways. At sea level, it is the pressure of air that causes water to boil at 100oC. Water can boil at a much lower temperature in vacuum, where there s no air. That is, if not for the skin that keeps the blood pressurized, body temperature would be sufficient to cause the blood to boil with water. At low air pressure the water boils significantly below 100oC at temperatures. The boiling point of water is the temperature at which the liquid water vapor pressure is equal to the pressure surrounding the body, and the body transforms into a vapour. The boiling point is the temperature for a particular liquid to boil at. For example, the boiling point for water, at a pressure of 1 atm, is 100 degrees Celsius. A liquid s boiling point depends upon the liquid s temperature, atmospheric pressure, and vapor pressure. Melting point of iceFor ice, the melting point is 0 C or 273K. The chemical element with the highest melting point is tungsten 3410 C , which is used for making filaments in light bulbs. During the melting process, till all the ice melts, the temperature of the system does not increase until after the melting point is reached. The whole of the supplied heat energy is consumed in increasing the potential energy of the ice molecules. The kinetic energy of the molecule does not increase further, and the temperature does not increase, so long as the melting continues. The quantity of heat required to completely change 1 kg of ice into water at atmospheric pressure at its melting point is called latent heat of fusion. METHODS OF SEPARATING MIXTURESMixtures can be separated from applying the following methods: a DecantationSediments can be separated from a liquid by pouring out the liquid. This process is called decantation. ExperimentPut some sand in a beaker. Add about 200cm3 of water. Allow sand to settle. Pour off water carefully into another beaker. ObservationSand settles at the bottom as sediments. Less clean water is poured out. ExplanationSand does not dissolve in water. Sand is denser than water and thus settles at the bottom as sediment. When poured out, the less dense water flows out.


ExplanationSand does not dissolve in water. Sand is denser than water and thus settles at the bottom as sediment. When poured out, the less dense water flows out. B FiltrationDecantation leaves suspended particles in the liquid after separation. Filtration is thus improved decantation. Filtration is the method of separating insoluble mixtures particles solids from a liquid. Experiment: To separate soil and water using filtrationFold a filter paper to fit well into a filter funnel. Place the funnel in an empty 250 cm3 beaker. Put one spatula end full of soil into 50cm3 of water. Stir. Put the soil water mixture into the filter funnel. ObservationsClean water is collected below the filter funnel. Soil remains above the filter paper. ExplanationA filter paper is porous which act like a fine sieve with very small holes. The holes allow smaller water particles to pass through but do not allow bigger soil particles. The liquid which passes through is called filtrate. The solid which do not pass through is called residue. Set up of apparatusIn industries, filtration is used in engine filters to clean up air. C EvaporationEvaporation is a method of separating a solute solid from its solution. This involves heating a solution solvent and solute to vapourize the solvent out of the solution mixture leaving pure solute solid. If a mixture contain insoluble solid, they are filtered out. Experiment: To separate a mixture of soil and salt sodium chloride . Procedure:Put one spatula end full of soil on a filter paper. Put one spatula full of common salt sodium chloride into the same filter paper. Mix well using the spatula,. Place about 200cm3 of water into a beaker. Put the contents of the filter paper into the water. Stir thoroughly using a glass stirring rod for about one minute. Fold a filter paper into a filter funnel. Pour half portion of the contents in the beaker into the filter funnel. Put the filtrate into an evaporating dish. Heat on a water bath. Observation i On mixingColourless crystals and brown soil particles appear on the filter paper. Ii On adding waterCommon soil dissolves in water. Soil particles do not dissolve in water. Iii On filtrationColourless liquid collected as filtrate below the filter funnel paper.


Ii On adding waterCommon soil dissolves in water. Soil particles do not dissolve in water. Iii On filtrationColourless liquid collected as filtrate below the filter funnel paper. Brown residue collected above the filter funnel paper. Iv On evaporationColourless crystals collected after evaporationExplanationSolid mixture of sand and common salt take the colors of the two. On adding water, common salt dissolves to form a solution. Soil does not because it is insoluble in water and thus forms a suspension. On filtration, a residue of insoluble soil does not pass through the filter paper. It is collected as residue. Common salt solution is collected as filtrate. On heating the filtrate, the solvent water evaporate vaporize out of the evaporating dish leaving common salt crystals. Vapourization evaporation can take place even without heating. This is the principle process of drying wet clothes on the hanging line. Set up of apparatus d DistillationDistillation is an improved evaporation where both the solute and the solvent in the solution are separated collected. Distillation therefore is the process of separating a solution into constituent solid solute and the solvent. It involves heating the solution to evaporate vaporize the solvent out. The solvent vapour is then condensed back to a liquid. Salty sea water can be made pure through simple distillation. Any mixture with a large difference 40oC in boiling point can be separated using simple distillation. E Fractional distillationFractional distillation is an improved simple distillation used specifically to separate miscible mixtures with very close near boiling points. Fractional distillation involves: i Heating the mixture in a conical round bottomed flat bottomed flask. The pure substance with a lower boiling point and thus more volatile evaporates boils vaporize first.e.g. Pure ethanol has a boiling point of 78oC.Pure water has a boiling point of 100 oC at sea level one atmosphere pressure. When a miscible mixture of ethanol and water is heated, ethanol vaporizes boils evaporates first because it is more volatile. Ii The conical round bottomed flat bottomed flask is connected to a long glass tube called fractionating column. The purpose of the fractionating column is to offer areas of condensation for the less volatile pure mixture.


When a miscible mixture of ethanol and water is heated, ethanol vaporizes boils evaporates first because it is more volatile. Ii The conical round bottomed flat bottomed flask is connected to a long glass tube called fractionating column. The purpose of the fractionating column is to offer areas of condensation for the less volatile pure mixture. The fractionating column is packed with glass beads broken glass porcelain shelves to increase the surface area of condensation of the less volatile pure mixture. Iii When the vapors rise they condense on the glass beads broken glass porcelain shelves which become hot. When the temperature of the glass beads broken glass porcelain shelves is beyond the boiling point of the less volatile pure substance, the pure substance rise and condensation take place on the glass beads broken glass porcelain shelves at a higher level on the fractionating column. The less volatile pure substance trickles drips back down the fractionating column or back into the conical round bottomed flat bottomed flask to be heated again. E.g. If the temperature on glass beads broken glass porcelain shelves is beyond 78oC, the more volatile pure ethanol rise to condense on the glass beads broken glass porcelain shelves higher in the fractionating column. Water condenses and then drip trickle to the glass beads broken glass porcelain shelves lower in the fractionating column because it is less volatile. Iv The fractionating column is connected to a Liebig condenser. The Liebig condenser has a cold water inlet and outlet circulation. The more volatile mixture that reach the top of the fractionating column is condenses by the Liebig condenser into a receiver. It is collected as the first fraction. V At the top of the fractionating column, a thermometer is placed to note monitor the temperature of the boiling mixtures. Pure substances have constant fixed boiling point. When one mixture is completely separated, the thermometer reading rises. E.g. the thermometer reading remains at78oC when ethanol is being separated. When no more ethanol is being separated, the mercury alcohol level in the thermometer rises. Vi The second subsequent fractions are collected in the receiver after noting a rise the mercury alcohol level in the thermometer. E.g. the thermometer reading rises to 100oC when water is being separated.


Vi The second subsequent fractions are collected in the receiver after noting a rise the mercury alcohol level in the thermometer. E.g. the thermometer reading rises to 100oC when water is being separated. It is passed through the Liebig condenser with the cold water inlet and outlet circulation. It is collected different receiver as the second subsequent fraction. Vii Each fraction collected should be confirmed from known physical chemical properties characteristic. ExampleEthanolEthanol is a colourless liquid that has a characteristic smell .When it is put in a watch glass then ignited, it catches fire and burn with a blue flame. WaterWater is a colourless liquid that has no smell odour .When it is put in a watch glass then ignited, it does not catch fire. Set up of apparatusIndustrial application of Fractional distillationOn a large scale,fractional distillation is used: i In fractional distillation of crude oil in an oil refinery. Crude oil is a mixture of many fractions. When heated in a furnace, the different fractions separate out according to their boiling point. In Kenya,fractional distillation takes place at Changamwe in Mombasa. Ii In fractional distillation of air. Air contain a mixture of three main useful gases which are condensed by cooling to very low temperature -200oC to form a liquid. The liquid is then heated. Nitrogen is the most volatile -196 oC and thus comes out as the first fraction. Argon at -186 oC is the second fraction. Oxygen at -183 oC is the last fraction. The three gases are very useful industrial gases. Sublimation depositionSome solids on heating do not melt to a liquid but change directly to a gas. The process by which a solid changes to a gas is called sublimation. The gas cools back and changes directly to a solid. The process by which a gas changes to a solid is called deposition. Sublimation and deposition therefore are the same but opposite processes.


The gas cools back and changes directly to a solid. The process by which a gas changes to a solid is called deposition. Sublimation and deposition therefore are the same but opposite processes. Some common substances that undergo sublimation deposition include: i Iodine ii Carbon IV oxide iii Camphor iv ammonium chloride v Iron III chloride vi Aluminum III chloride vii benzoic acidIf a mixture has any of the above as a component, then on heating it will change to a gas and be deposited away from the source of heating. ProcedurePlace about one spatula full of ammonium chloride crystals into a clean dry 100cm3 beaker. Add equal amount of sodium chloride crystals into the beaker. Swirl to mix. Place the beaker on a tripod stand. Put about 100cm3 of water into another beaker. Place carefully the beaker containing water on top of the beaker containing the solid mixture. Light ignite a burner and heat the solid. Set up of apparatus:Observation i With ammonium chloride common salt mixtureWhite fumes produced. White sublimate depositedColourless residue left ii With Iodine common salt mixturePurple fumes produced. Dark grey sublimate depositedColourless residue leftExplanation i On heating a mixture of ammonium chloride and common salt, a white fume of ammonium chloride is produced. The white fumes solidify as white sublimate on the cooler parts. Common salt remains as residue. Chemical equation:Ammonium chloride solid Ammonium chloride gas ii On heating a mixture of Iodine and common salt, a purple fume of Iodine vapour is produced. The purple fumes solidify as dark grey sublimate on the cooler parts. Common salt remains as residue. Chemical equation:Iodine solid Iodine gasChromatographyChromatography is a method of separating components of a solution mixture by passing it through a medium where the different components move at different rates. The medium through which the solution mixture is passed is called absorbent material. Paper chromatography is a method of separating colored dyes by using paper as the absorbent material. Since dyes are insoluble do not dissolve in water, ethanol and propanone are used as suitable solvents for dissolving the dye.


The medium through which the solution mixture is passed is called absorbent material. Paper chromatography is a method of separating colored dyes by using paper as the absorbent material. Since dyes are insoluble do not dissolve in water, ethanol and propanone are used as suitable solvents for dissolving the dye. Practically, a simple paper chromatography involve placing a dye material on the absorbent material, adding slowly a suitable soluble solvent on the dye material using a dropper, the solvent spread out on the absorbent material carrying the soluble dye away from the origin. The spot on which the dye is initially originally placed is called baseline. The farthest point the solvent spread is called solvent front. The farthest a dye can be spread by the solvent depend on: i Density of the dye-the denser the dye, the less it spread from the basely ne by the solvent. Ii Stickiness of the dye-some dyes sticks on the absorbent material more than other thus do not spread far from baseline. Experiment: To investigate the colors in inkProcedureMethod 1Place a filter paper on an empty beaker. Put a drop of black blue ink in the centre of the filter paper. Wait for about one minute for the ink drop to spread. Using a clean teat pipette dropper add one drop of ethanol propanone. Wait for about one minute for the ink drop to spread further. Add about twenty other drops of ethanol waiting for about one minute before each addition. Allow the filter paper to dry. Experiment: To investigate the colors in inkProcedureMethod 2Cut an 8 centimeter thin strip of a filter paper. At about 3cm on the strip, place a drop of ink. Place the filter paper in a 10cm length boiling tube containing 5cm3 of ethanol. Ensure the cut strip of the filter paper just dips into the ethanol towards the ink mark. Cover the boiling tube. Wait for about twenty minutes. Remove the boiling tube and allow the filter paper to dry. Set up of apparatusExplanationWhen a drop of ink is placed on an absorbent material it sticks. On adding an eluting solvent, it dissolves the dye spread out with it. The denser and sticky pure dye move least. The least dense sticky pure dye move farthest. A pure dye will produce the same chromatogram spot if the same eluting solvent is used on the same absorbent material.


The denser and sticky pure dye move least. The least dense sticky pure dye move farthest. A pure dye will produce the same chromatogram spot if the same eluting solvent is used on the same absorbent material. Comparing the distance moved by a pure dye with a mixture, the coloured dyes in a mixture can be deduced as below:Example 1The chromatogram of pure dyes A, B ,C and a dye mixture D is shown below Determine the pure dyes present in D. On the diagram show: i the solvent front ii Baseline Iii the most soluble pure dye i Solvent extractionSolvent extraction is a method of separating oil from nuts seeds. Most nuts contain oil. First the nuts are crushed to reduce their size and increase the surface area. A suitable volatile solvent is added. The mixture is filtered. The filtrate solvent is then allowed to crystallize leaving the oil fat. If a filter paper is rubbed smeared with the oil fat, it becomes translucent. This is the test for the presence of oil fat. Experiment: To extract oil from Macadamia nut seedsProcedureCrush Macadamia nut seeds form the hard outer cover .Place the inner soft seed into a mortar. Crush add a little sand to assist in crushing . Add a little propanone and continue crushing. Continue crushing and adding a little propanone until there is more liquid mixture than the solid. Decant filter. Put the filtrate into an evaporating dish. Vapourize the solvent using solar energy sunlight. Smear rub a portion of the residue left after evaporation on a clean dry filter paper. Observation ExplanationPropanone dissolve fat oil in the macadamia nuts. Propanone is more volatile lower boiling point than oil fat. In sunlight solar energy, propanone evaporate vaporize leaving oil fat has a higher boiling point .Any seed like corn, wheat , rice, soya bean may be used instead of macadamia seed. When oil fat is rubbed smeared on an opaque paper, it becomes translucent. CrystallizationCrystallization is the process of using solubility of a solute solid to obtain the solute solid crystals from a saturated solution by cooling or heating the solution. A crystal is the smallest regular shaped particle of a solute.


When oil fat is rubbed smeared on an opaque paper, it becomes translucent. CrystallizationCrystallization is the process of using solubility of a solute solid to obtain the solute solid crystals from a saturated solution by cooling or heating the solution. A crystal is the smallest regular shaped particle of a solute. Every solute has unique shape of its crystals. Some solutions form crystals when heated. This is because less solute dissolves at higher temperature. Some other solutions form crystals when cooled. This is because less solute dissolves at lower temperature. Experiment; To crystallize copper II sulphate VI solutionProcedure:Place about one spatula full of hydrated copper sulphate VI crystals into 200cm3 of distilled water in a beaker. Stir. Continue adding a little more of the hydrated copper sulphate VI crystals and stirring until no more dissolve. Decant filter. Cover the filtrate with a filter paper. Pierce and make small holes on the filter paper cover. Preserve the experiment for about seven days. Observation ExplanationLarge blue crystals formedWhen hydrated copper II sulphate crystals are placed in water, they dissolve to form copper II sulphate solution. After some days water slowly evaporate leaving large crystals of copper II sulphate. If the mixture is heated to dryness, small crystals are formed. Using MagnetsMixtures containing substances that are attracted by magnets can be separated using a magnet. We can separate iron from a mixture of sand and iron, as only the iron is attracted to the magnet. ACIDS, BASES AND INDICATORSIn a school laboratory: i An acid may be defined as a substance that turns litmus red. Ii A base may be defined as a substance that turns litmus blue. Litmus is lichen found mainly in West Africa. It changes its colour depending on whether the solution it is in, is basic alkaline or acidic. It is thus able to identify show whether another substance is an acid, base or neutral. Iii An indicator is a substance that shows whether another substance is a base alkaline,acid or neutralCommon naturally occurring acids include:Most commonly used acids found in a school laboratory are not naturally occurring. They are manufactured. They are called mineral acids. Common mineral acids include:Mineral acids are manufactured to very high concentration.


They are manufactured. They are called mineral acids. Common mineral acids include:Mineral acids are manufactured to very high concentration. They are corrosive causes painful wounds on contact with the skin and attack reacts with garments clothes metals. In a school laboratory, they are mainly used when added a lot of water. This is called diluting. Diluting ensures the concentration of the acid is safely low. Bases are opposite of acids. Most bases do not dissolve in water. Bases which dissolve in water are called alkalis. Common alkalis include:Common bases which are not alkali include:Indicators are useful in identifying substances which look-alike. An acid-base indicator is a substance used to identify whether another substance is alkaline or acidic. An acid-base indicator works by changing to different colors in neutral, acidic and alkaline solutions dissolved in water. Experiment: To prepare simple acid-base indicatorProcedure a Place some flowers petals in a mortar. Crush them using a pestle. Add a little sand to assist in crushing. Add about 5cm3 of propanone ethanol and carefully continue grinding. Add more 5cm3 of propanone ethanol and continue until there is enough extract in the mortar. Filter the extract into a clean 100cm3 beaker. B Place 5cm3 of filtered wood ash, soap solution, ammonia solution, sodium hydroxide, hydrochloric acid, distilled water, sulphuric VI acid, sour milk, sodium chloride, toothpaste and calcium hydroxide into separate test tubes. C Put about three drops of the extract in a to each test tube in b . Record the observations made in each case. Sample observationsThe plant extract is able to differentiate between solutions by their nature. It is changing to a similar colour for similar solutions. I Since lemon juice is a known acid, then sulphuric VI and hydrochloric acids are similar in nature with lemon juice because the indicator shows similar colors. They are acidic in nature. Ii Since sodium hydroxide is a known base alkali, then the green colour of indicator shows an alkaline basic solution. Iii Since pure water is neutral, then the orange colour of indicator shows neutral solutions. In a school laboratory, commercial indicators are used. A commercial indicator is cheap, readily available and easy to store.


Iii Since pure water is neutral, then the orange colour of indicator shows neutral solutions. In a school laboratory, commercial indicators are used. A commercial indicator is cheap, readily available and easy to store. Common indicators include: Litmus, phenolphthalein, methyl orange, screened methyl orange, bromothymol blue. Experiment:Using commercial indicators to determine acidic, basic alkaline and neutral solutionsProcedurePlace 5cm3 of the solutions in the table below. Add three drops of litmus solution to each solution. Repeat with phenolphthalein indicator, methyl orange, screened methyl orange and bromothymol blue. Sample resultsThe universal indicatorThe universal indicator is a mixture of other indicator dyes. The indicator uses the pH scale. The pH scale shows the strength of bases and acids. The pH scale ranges from 1-14.These numbers are called pH values: i pH values 1, 2, 3 shows a substance is strongly acid ii pH values 4, 5, 6 shows a substance is a weakly acid iii pH value 7 shows a substance is a neutral iv pH values 8, 9, 10, 11 shows a substance is a weak base alkali. V pH values 12, 13, 14 shows a substance is a strong base alkaliThe pH values are determined from a pH chart. The pH chart is a multicolored paper with each colour corresponding to a pH value.i.e i red correspond to pH 1, 2, 3 showing strongly acidic solutions. Ii Orange yellow correspond to pH 4, 5, 6 showing weakly acidic solutions. Iii Green correspond to pH 7 showing neutral solutions. Iv Blue correspond to pH 8, 9, 10, 11 showing weakly alkaline solutions. V Purple dark blue correspond to pH 12,13,14 showing strong alkalis. The universal indicator is available as: i Universal indicator paper pH paper ii Universal indicator solution. When determining the pH of a unknown solution using i pH paper then the pH paper is dipped into the unknown solution. It changes turn to a certain colour. The new colour is marched compared to its corresponding one on the pH chart to get the pH value.


A woman is generally most likely to get pregnant fertile if she has sex a few days before, and during ovulation. Menstrual CycleEach month during the years between puberty and menopause, a woman s body goes through a number of changes to get it ready for a possible pregnancy. This series of hormone-driven events is called the menstrual cycle. During each menstrual cycle, an egg develops and is released from the ovaries. The lining of the uterus builds up. If a pregnancy doesn t happen, the uterine lining sheds during a menstrual period. Then the cycle starts again. Menstrual phaseThe menstrual phase is the first stage of the menstrual cycle. It s also when you get your period. This phase starts when an egg from the previous cycle isn t fertilized. Because pregnancy hasn t taken place, levels of the hormones estrogen and progesterone drop. The thickened lining of your uterus, which would support a pregnancy, is no longer needed, so it sheds through your vagina. During your period, you release a combination of blood, mucus, and tissue from your uterus. You may have period symptoms like these:crampstender breastsbloatingmood swingsirritabilityheadachestirednesslow back painOn average, women are in the menstrual phase of their cycle for 3 to 7 days. Some women have longer periods than others. Identifying common issues related to Menstrual cycleEvery woman s menstrual cycle is different. Some women get their period at the same time each month. Others are more irregular. Some women bleed more heavily or for a longer number of days than others. Your menstrual cycle can also change during certain times of your life. For example, it can get more irregular as you get close to menopause. One way to find out if you re having any issues with your menstrual cycle is to track your periods. Write down when they start and end. Also record any changes to the amount or number of days you bleed, and whether you have spotting between periods. Any of these things can alter your menstrual cycle:Birth control. The birth control pill may make your periods shorter and lighter. While on some pills, you won t get a period at all. Pregnancy. Your periods should stop during pregnancy. Missed periods are one of the most obvious first signs that you re pregnant. Uterine fibroids.


Your periods should stop during pregnancy. Missed periods are one of the most obvious first signs that you re pregnant. Uterine fibroids. These noncancerous growths in your uterus can make your periods longer and heavier than usual. Eating disorders. Anorexia, bulimia, and other eating disorders can disrupt your menstrual cycle and make your periods stop. Here are a few signs of a problem with your menstrual cycle:You ve skipped periods, or your periods have stopped entirely. Your periods are irregular. You bleed for more than seven days. Your periods are less than 21 days or more than 35 days apart. You bleed between periods heavier than spotting . If you have these or other problems with your menstrual cycle or periods, talk to your healthcare provider. Managing issues related to the menstrual cyclestopping smokingusing heating pads, hot water bottles, or warm baths to ease paintrying gentle forms of exercise, such as walkingmanaging stress and making time for relaxationavoiding caffeine, alcohol, and refined sugar in the 2 weeks before a periodgetting enough sleep each nightFertilization and implantation in human beings Fertilization in humans refers to the fusion of male and female gametes that facilitates the development of a new organism. Fertilization is the natural life process, which is carried out by the fusion of both male and female gametes, which results in the formation of a zygote. In humans, the process of fertilization takes place in the fallopian tube. During this process, semen comprising thousands of sperms are inseminated into the female vagina during coitus. The sperms move towards the uterus and reach the opening of the fallopian tube. Only a few sperms will succeed in reaching the opening of the fallopian tube. Both sperm and egg can show their vitality only to a limited period. Sperm is alive for 48-72 hours in a female reproductive system, whereas the egg can be fertilized for 24 hours before it is released. Only one sperm will succeed in fertilising the ovum, by penetrating its cell membrane and depositing the male genetic material into the female cell, where the two nuclei fuse. The fertilised ovum zygote immediately becomes resistant to penetration by any other sperm arriving later.