Chapter 1Chapter 1

Introduction TO ScienceIntroduction TO Science

What is Science?What is Science?

1.1. The definition of science is "knowledge The definition of science is "knowledge attained through study or practice," attained through study or practice,"

2.2. Science is the systematic study of nature Science is the systematic study of nature and its effects on us and the and its effects on us and the environment.environment.

3.3. It is the study of natural phenomena.It is the study of natural phenomena.4.4. Science helps us find out about Science helps us find out about

ourselves, plants and animals, our ourselves, plants and animals, our environment and things around us.environment and things around us.

5.5. Scientific knowledge is always growing. Scientific knowledge is always growing. What we learn in science today is a What we learn in science today is a result of many years of study.result of many years of study.

6.6. Science helps us understand natural Science helps us understand natural phenomena. Every natural phenomenon phenomena. Every natural phenomenon makes us wonder why it happens. makes us wonder why it happens. Discovering the answers leads us to new Discovering the answers leads us to new scientific knowledge.scientific knowledge.

Read itRead it Science is a continuing effort to discover and Science is a continuing effort to discover and

increase human _______ and understanding increase human _______ and understanding through disciplined research. Using controlled through disciplined research. Using controlled methods, scientists collect _______ evidence of methods, scientists collect _______ evidence of natural or social _______, record measurable natural or social _______, record measurable ________ relating to the _______, and analyze ________ relating to the _______, and analyze this information to construct _________ this information to construct _________ explanations of how things work. The methods explanations of how things work. The methods of scientific research include the generation of of scientific research include the generation of _______ about how phenomena work, and _______ about how phenomena work, and _____________ that tests these hypotheses _____________ that tests these hypotheses under controlled conditions under controlled conditions

Read itRead it Science is a continuing effort to discover and increase Science is a continuing effort to discover and increase

human khuman knowledgnowledge and understanding through disciplined e and understanding through disciplined research. Using controlled methods, scientists collect research. Using controlled methods, scientists collect observable evidence of natural or social phenomena, observable evidence of natural or social phenomena, record measurable data relating to the observations, and record measurable data relating to the observations, and analyze this information to construct theoretical analyze this information to construct theoretical explanations of how things work. The methods of explanations of how things work. The methods of scientific research include the generation of hypotheses scientific research include the generation of hypotheses about how phenomena work, and experimentation that about how phenomena work, and experimentation that tests these hypotheses under controlled conditions tests these hypotheses under controlled conditions

Natural PhenomenaNatural Phenomena

Natural phenomena are fascinating.Natural phenomena are fascinating.Examples of a natural phenomenon are Examples of a natural phenomenon are

a baby growing up and becoming an adult,a baby growing up and becoming an adult, ice can melt.ice can melt.

We want to know why these things We want to know why these things happen. We search for answers.happen. We search for answers.

The study of science gives us these The study of science gives us these answers. Science covers everything in the answers. Science covers everything in the universe.universe.

Importance of Science in Everyday LifeImportance of Science in Everyday Life

1.1. Every aspect of our life is related to science. For Every aspect of our life is related to science. For example, our food and clothes are produced using example, our food and clothes are produced using scientific knowledge.scientific knowledge.

2.2. Scientific discoveries make our lives more comfortable. Scientific discoveries make our lives more comfortable. With scientific knowledge we can produce machines With scientific knowledge we can produce machines and appliances such as light bulbs, cars and computers.and appliances such as light bulbs, cars and computers.

3.3. Science helps us to understand our environment. We Science helps us to understand our environment. We can use this knowledge wisely. For example, we can can use this knowledge wisely. For example, we can recycle paper. This is one way to conserve our recycle paper. This is one way to conserve our resources. It protects our environment by reducing the resources. It protects our environment by reducing the number of trees that need to be cut down to make number of trees that need to be cut down to make paper.paper.

4.4. We can create scientific knowledge and also use it. We We can create scientific knowledge and also use it. We can manufacture plastic and synthetic materials. These can manufacture plastic and synthetic materials. These are used to make many different objects such as pipes, are used to make many different objects such as pipes, umbrellas, toys and furniture.umbrellas, toys and furniture.

5.5. We have invented instruments such as spectacles, the We have invented instruments such as spectacles, the microscope and the telescope. These help us to see microscope and the telescope. These help us to see better. The stethoscope enables us to hear better.better. The stethoscope enables us to hear better.

6.6. The application of scientific knowledge is called The application of scientific knowledge is called technology. Technology helps us to introduction to technology. Technology helps us to introduction to Science progress in every aspect of our lives. Science progress in every aspect of our lives.

TransportTransport

Transport is easier, faster, more Transport is easier, faster, more comfortable and safer today than it used to comfortable and safer today than it used to be.be.

CommunicationCommunication

1.1. The telephone, facsimile, radio, television and The telephone, facsimile, radio, television and computer help us to communicate with one computer help us to communicate with one another. The launching of communication another. The launching of communication satellites makes long distance communication satellites makes long distance communication possible.possible.

2.2. Information Communication Technology Information Communication Technology (ICT) is very important in developing the (ICT) is very important in developing the industrial, medical, trade and administrative industrial, medical, trade and administrative sectors of a nation.sectors of a nation.

AgricultureAgriculture

1.1. Technology helps us to produce more food.Technology helps us to produce more food.

2.2. Machines have been invented to do most of the Machines have been invented to do most of the heavy and difficult work. Ploughing, scattering heavy and difficult work. Ploughing, scattering of seeds, harvesting and crushing can now be of seeds, harvesting and crushing can now be done by machines easily and quickly.done by machines easily and quickly.

3.3. By using modern fertilizers and insecticides, we By using modern fertilizers and insecticides, we can increase agricultural production.can increase agricultural production.

ConstructionConstruction

1.1. In the past, houses and buildings were made from In the past, houses and buildings were made from materials found close by. This means only small and materials found close by. This means only small and simple buildings could be built.simple buildings could be built.

2.2. As we progress, we require bigger buildings and more As we progress, we require bigger buildings and more complex structures. We need, for example, office complex structures. We need, for example, office blocks, apartments, stadiums and airports.blocks, apartments, stadiums and airports.

3.3. Strong bridges need to be built over rivers. To prevent Strong bridges need to be built over rivers. To prevent flooding, we need to build dams. Dams also generate flooding, we need to build dams. Dams also generate electricity. More importantly, they supply water to electricity. More importantly, they supply water to millions of people in the cities. Today, we have millions of people in the cities. Today, we have developed stronger building materials for building dams. developed stronger building materials for building dams. Steel, concrete and reinforced glass are some Steel, concrete and reinforced glass are some examples of strong materials used in construction examples of strong materials used in construction today.today.

SpellingSpelling Natural phenomenaNatural phenomena Scientific knowledgeScientific knowledge TechnologyTechnology TransportTransport CommunicationCommunication AgricultureAgriculture PhysiologyPhysiology PrecautionsPrecautions HypothesesHypotheses observable evidenceobservable evidence

MedicineMedicine

1.1. A century ago, people rarely lived beyond 30 or 40 A century ago, people rarely lived beyond 30 or 40 years. Today, we can live beyond 70 years because of years. Today, we can live beyond 70 years because of the progress in the medical field.the progress in the medical field.

2.2. The invention of X-ray machines, lasers, The invention of X-ray machines, lasers, electrocardiogram (ECG) and dialysis machines have electrocardiogram (ECG) and dialysis machines have helped to save the lives of many patients. Medical helped to save the lives of many patients. Medical operations have become easier and safer.operations have become easier and safer.

3.3. The discovery of new medicines, vaccines and The discovery of new medicines, vaccines and antibiotics have also helped to save lives. They reduce antibiotics have also helped to save lives. They reduce the pain and suffering of patients. They help to cure and the pain and suffering of patients. They help to cure and prevent many diseases and illnesses.prevent many diseases and illnesses.

Careers in ScienceCareers in Science

Doctor - someone trained in medical Doctor - someone trained in medical science.science.

Engineer - a person who designs, builds Engineer - a person who designs, builds and maintains engines, buildings or roads.and maintains engines, buildings or roads.

Nurse - a specialist in caring of patients.Nurse - a specialist in caring of patients.Veterinarian - an animal doctor.Veterinarian - an animal doctor.Architect - a person who designs Architect - a person who designs

buildings.buildings.

Pharmacist - someone trained in the field Pharmacist - someone trained in the field of medicine and drugs.of medicine and drugs.

Chemist - someone trained in chemistry.Chemist - someone trained in chemistry.Computer programmer - a developer of Computer programmer - a developer of

computer software programmes.computer software programmes.

Study of ScienceStudy of Science Astronomy - the study of planets and stars.Astronomy - the study of planets and stars. Biology - the study of life.Biology - the study of life. Physics - the study of matter and energy.Physics - the study of matter and energy. Biology - the study of processes and functions of Biology - the study of processes and functions of

systems in the human body.systems in the human body. Geology - the study of rocks and minerals.Geology - the study of rocks and minerals. Meteorology - the study of weather and climate.Meteorology - the study of weather and climate. Chemistry - the study of the composition and Chemistry - the study of the composition and

chemical properties of substances.chemical properties of substances. Biotechnology - the study of the industrial use of Biotechnology - the study of the industrial use of

living organisms.living organisms. Biochemistry - the study of chemical substances Biochemistry - the study of chemical substances

and chemical processes of living things.and chemical processes of living things.

Exercise 1.1Exercise 1.1 Indicate with a tick (Indicate with a tick () the correct examples of ) the correct examples of

natural phenomena.natural phenomena. Eating a lot of food makes you fat.Eating a lot of food makes you fat. You feel tired and sleepy in a hot and crowded You feel tired and sleepy in a hot and crowded

classroom.classroom. Food cooked in an earthen pot tastes better than food Food cooked in an earthen pot tastes better than food

cooked in a metal pot.cooked in a metal pot. Using salt to preserve fish.Using salt to preserve fish. Seeing flashes of lightning first, before hearing Seeing flashes of lightning first, before hearing

thunder.thunder. Families today have fewer children.Families today have fewer children. Saving money in a bank.Saving money in a bank. Painting a bicycle to make it last longer.Painting a bicycle to make it last longer.

2.2. Give two' examples of developments in Give two' examples of developments in the fields of medicine and the fields of medicine and telecommunications.telecommunications.

3.3. What is the difference between 'science' What is the difference between 'science' and 'technology'?and 'technology'?

4.4. (a) State two areas of study in science.(a) State two areas of study in science. (b) Give two applications of your answer (b) Give two applications of your answer

in (a).in (a).

Question 5Question 5State the field of science involved in the State the field of science involved in the

following situations:following situations:Discovering a cure for lung cancer Discovering a cure for lung cancer Discovering a new medicine from a jungle Discovering a new medicine from a jungle

plantplantConstructing a building that cannot be Constructing a building that cannot be

damaged by earthquakesdamaged by earthquakesDiscovering a new petroleum field under the Discovering a new petroleum field under the

seaseaDiscovering how a hormone affects human Discovering how a hormone affects human

growthgrowth

1.2 A science Laboratory1.2 A science Laboratory

1. Scientists can work anywhere. A scientist studying tropical plants and animals for example, could make the Malaysian jungle his laboratory. However, most scientists do their experiments in a laboratory.

2. However, some chemicals are dangerous. We need to handle these chemicals carefully. We need to know about safety in the laboratory.

1-10-091-10-09

Discipline in the science laboratory

1. No pupil is allowed to enter the laboratory without the teacher's permission.

2. If the class arrives before the teacher, line up outside the laboratory and wait quietly.

3. After entering the laboratory, go to your places in an orderly manner.

4. No food or drink should be taken into the laboratory.

5. Nothing is to be taken from the laboratory.6. When in doubt ask your teacher for help and

advice.

Safety rules in the science laboratory

1. Pupils must not carry out experiments without the teacher's permission.

2. Read and understand the instructions given before you attempt to do the experiment. When in doubt always ask your teacher.

3. Handle all apparatus correctly and carefully.4. Do not light a Bunsen burner with a piece of

paper. Turn off the gas after use.5. Do not play or walk around unnecessarily in the

laboratory.

6. Always read the label on the bottle before using the chemical it contains.

7. Do not handle chemicals with your fingers. Always use a spatula.

8. Do not waste any chemical. Use only the required amount.

9. Do not pour any excess chemical back into the reagent bottle.

10. When heating any solution in a boiling tube, always make sure that the mouth of the tube is not pointed towards anybody.

11. Water, gas and electricity must not be wasted.

12. Solid wastes must be put in the bins provided. Do not throw solid wastes into the sinks.

13. Do not taste any chemical or inhale any gas.

14. Breakages and faulty equipments must be reported to the teacher at once.

15. Any mishaps, cuts, burns, scalds or substances which get into your mouth must be reported to the teacher at once.

16. Do not damage any fitting or the electrical mains in the laboratory.

17. When the practical periods are over, wash all used apparatus and return them to their respective places.

18. Wash your hands thoroughly.

19. The benches must be left clean and tidy.

20. All taps and switches must be turned off.

Some simple rules and precautionsSome simple rules and precautions

Do not heat a gas jar directly with a Bunsen flame.

Correct way of inhaling gas. Read the label on the bottle before using the

chemical inside. Never point the mouth of the boiling tube

towards anybody when heating. Do not stand too close to the flame when

heating up a solution. Tie your hair neatly when doing experiments.

Accidents and First AidAccidents and First Aid Inflammable liquid: If an inflammable liquid is

spilt, put out all flames immediately. Minor cuts and abrasions: Apply tincture of

iodine on a pad of cotton wool. Cover with sterilized dressing.

Deep cuts: Apply a thick pad of gauze or cotton wool over the wound. Send the person to a doctor or a nearby clinic.

Scalds: Bathe the affected part with a warm saturated solution of sodium carbonate.

Burns: It is best for the teacher to send the person to a doctor or a clinic.

6. Poisoning: Should a chemical or a liquid get into your mouth, spit it out into the sink. Rinse your mouth with plenty of water. Consult a doctor at once.

7. Acid: If you have swallowed an acid, rinse your mouth with plenty of water. Then milk of magnesia (or dilute lime-water) should be taken. Consult a doctor at once.

8. Alkali: If you have swallowed an alkali, rinse your mouth with plenty of water. Then lemon juice (or 1% acetic acid) should be taken. Consult a doctor immediately.

9. Eye injuries: If due to an acid or an alkali, wash with plenty of water. Any injury to the eyes must be attended to by a doctor immediately.

10. Electric shock: The electric current must be switched off immediately. With the help of an insulator, get the victim away from the source of electric current. In serious cases artificial respiration may be required

Hazordous SymbolsHazordous Symbols

1. (Mixture of hydrogen and air, nitrates, sodium, potassium) Keep away from fire or

heat sources.

2. (Petrol, kerosene, ethanol, white phosphorus, yellow phosphorus) Keep away from fire or

heat sources.

8-10-098-10-091. Mercury, lead, chlorine,

sodium cyanide, hydrogen sulphide. Keep in a locked

cupboard.

2. Concentrated acids and alkalis, bromine, hydrogen peroxide. Be careful not to spill onto

your clothes or yourself. If accidentally spilt, wash quickly with lots of water.

1. Ammonia, dilute acids, chloroform, alcohol, bromine Be careful not to spill onto

your clothes or yourself. If accidentally spilt, wash quickly with lots of water.

2. Uranium, plutonium, radium, radioactive carbon Keep in special lead

containers.

Common Laboratory ApparatusCommon Laboratory Apparatus

Common Laboratory ApparatusCommon Laboratory Apparatus

Way to Use Bunsen BurnerWay to Use Bunsen Burner

1.1. Close the air hole completely by turning Close the air hole completely by turning the collar.the collar.

2.2. Hold a lighted match or wooden splinter Hold a lighted match or wooden splinter near the mouth of the barrel.near the mouth of the barrel.

3.3. Turn on the gas slowly.Turn on the gas slowly.

4.4. When the flame is seen, slowly open the When the flame is seen, slowly open the air hole by turning the collar.air hole by turning the collar.

Bunsen Burner Bunsen Burner

FLAME FLAME

Luminous flame vs Non-luminous flame

a. Yellow

b. Easy to see

c. Produces a lot of soot.

d. Shape changes

e. Not very hot

f. Incomplete burning

g. Not suitable for heating

a. Blue

b. Not easy to see

c. Does not produce soot

d. Constant shape

e. Very hot

f. Complete burning

g. Suitable for heating

Bunsen BurnerBunsen Burner

1. The Bunsen burner gives different flames under different conditions. When the air hole is closed, a yellow flame is produced. This is called a luminous flame. This flame is easy to see. It produces a lot of soot.

2. When the air-hole is opened, a blue flame is produced. It is called a non-luminous flame.

1.3 The Steps in a scientific 1.3 The Steps in a scientific InvestigationInvestigation1. Identify problem

2. Form a hypothesis3. Plan investigation (experiment)

4. Control variables5. Collect data

6. Analyse data7. Interpret data

8. Make conclusions9. Results support hypothesis or Results do not support

hypothesis10. Prepare report

Activity: The Pendulum experimentActivity: The Pendulum experiment

The steps in the scientific method for the experiment on the swing of a pendulum.

1. The problem and hypothesis are determined at the beginning.

2. (a) The manipulated variable is the pendulum length. (b) The responding variable is the period of swing. (c) The fixed variable constant is the pendulum

weight.3. The time recorded is based on actual observations.

It was not guess work.4. The conclusion is drawn based on the analysis of

the data obtained.

Exercise 1.2 Exercise 1.2

1. Complete the following correctly. The way of getting scientific knowledge is known as

_______. An opinion that is considered true, although it is not yet

tested is a _______. The aim of carrying out an experiment is to collect

_____. From the data collected, a scientist is able to _____,

and from here_____ about the investigation that is carried out.

Planning the investigation • Making a conclusion Identifying the problem • Interpreting data Collecting data • Making a hypothesis

Question 2Question 2

1. In the pendulum experiment, state the manipulated variable responding variable variable that is kept constant

b. State what the effect will be on the time taken for one complete swing, when the length of the pendulum is increased.

1.4 Physical Quantities and Their Units1.4 Physical Quantities and Their Units

1. A physical quantity is a quantity that can be measured. Examples of physical quantities are length, time, mass, temperature and electric current.

2. Physical quantities are measured in S.I. units. The S.I. symbol is an abbreviation for the French term Systeme International d'Unites. It means International System of Units.

Basic QuantitiesBasic Quantities

Physical quantity S.I. unit Symbol Instrument

Length Metre m Metre rule

Mass Kilogram kgLever or beam balance

Time Second sStop clock or stop watch

Temperature Kelvin K Thermometer

Electric Current  Ampere A Ammeter 

Prefixes Used in MeasurementPrefixes Used in Measurement

1. Prefixes are useful in expressing physical quantities that are either very big or very small.

2. The value of any physical quantity can be changed to prefix form. See the examples below.

Write 840 000 g with the kilo prefix. 840 000 / 1000 = 840 kg

Symbol and PrefixesSymbol and Prefixes

Physical quantities and prefixes

Value of physical quantity Prefix form

0.005 m 5 mm

250 g 0.25 kg

4 000 000 K 4 MK

0.000 003 A 3 чA

Exercise 1.4Exercise 1.4

1.1.Complete the table….Complete the table….

2. State the symbol and value for the tollowir, prefixes.

Mega:_______ Kilo: ________ Milli: ________

1.5 Measuring Tools1.5 Measuring Tools

Measuring the length of an objectMeasuring the length of an object If the position of the eye is at A or C, the If the position of the eye is at A or C, the

reading taken is not accurate. This error is reading taken is not accurate. This error is known as known as parallax errorparallax error..

Measuring the length of a straight lineMeasuring the length of a straight lineThe lengths are measured by taking several The lengths are measured by taking several

readings. The average length is then readings. The average length is then determined.determined.

Measuring the length of a curveMeasuring the length of a curve Some thread and a ruler are used for measuring the Some thread and a ruler are used for measuring the

length of a curve.length of a curve. The thread is placed along the length of the curve The thread is placed along the length of the curve PQ. PQ.

The end of the curve is marked on the thread.The end of the curve is marked on the thread. The length of the thread is later measured using the The length of the thread is later measured using the

metre rule.metre rule. The length of the curve is measured three times. The length of the curve is measured three times.

Then the average length is determined.Then the average length is determined. The length of the curve can also be measured using The length of the curve can also be measured using

an opisometer and a metre rule.an opisometer and a metre rule.

Opisometer Opisometer

Measuring the external diameter Measuring the external diameter of a beakerof a beaker

Measuring the external diameter Measuring the external diameter of a beakerof a beaker

Measurement of AreaMeasurement of Area

1.1. The S.I. unit for area is square metres The S.I. unit for area is square metres (m(m22).).

2.2. The area of objects with regular shapes The area of objects with regular shapes such as rectangles, triangles and circles such as rectangles, triangles and circles are calculated using mathematical are calculated using mathematical formulae.formulae.

3.3. The area of irregular shaped objects can The area of irregular shaped objects can be estimated by using graphbe estimated by using graph

Measurement of VolumeMeasurement of Volume

1.1. The S.I. unit for volume is cubic metres, The S.I. unit for volume is cubic metres, (m(m33).).

2.2. All these units can be used to measure All these units can be used to measure the volume of liquids. However, the the volume of liquids. However, the volume of liquids is usually measured in volume of liquids is usually measured in metric unit i.e. litre metric unit i.e. litre (l) and millilitre (ml).(l) and millilitre (ml).

3.3. The volume of The volume of solids is measured in solids is measured in cmcm33 and and mm3 3 units.units.

Volume of liquidsVolume of liquids The measuring cylinder must be placed on a flat The measuring cylinder must be placed on a flat

surface.surface. The level of the liquid in a measuring cylinder is The level of the liquid in a measuring cylinder is

curved downwards. This curve is called the curved downwards. This curve is called the meniscus.meniscus.

Your eye, must be at the same level as the bottom Your eye, must be at the same level as the bottom of the meniscus when reading the volume.of the meniscus when reading the volume.

This must be done for all liquids except for This must be done for all liquids except for mercury where the meniscus curves upwards. The mercury where the meniscus curves upwards. The correct eye position prevents parallax errors.correct eye position prevents parallax errors.

Measuring liquids Measuring liquids

Using a pipetteUsing a pipetteUsing a buretteUsing a burette

Volume of SolidsVolume of SolidsWater DisplacementWater Displacement

Measuring the volume of irregular Measuring the volume of irregular solids with a eureka tinsolids with a eureka tin

Choosing Suitable Measuring Choosing Suitable Measuring InstrumentsInstruments

1.1. Measuring instruments measure definite Measuring instruments measure definite quantities.quantities.

2.2. All measurements made are only close All measurements made are only close estimates of the values of the quantities. estimates of the values of the quantities. They cannot be 100% accurate.They cannot be 100% accurate.

3.3. We need to consider how precise and We need to consider how precise and accurate a measurement is.accurate a measurement is.

AccuracyAccuracy1.1. The accuracy of a measurement is how close the The accuracy of a measurement is how close the

measured value is to the real value.measured value is to the real value.

2.2. The difference between the measured value and the The difference between the measured value and the real value is the error in the reading. If the error real value is the error in the reading. If the error between the measured value and the real value is between the measured value and the real value is small, the measurement is precise.small, the measurement is precise.

3.3. The accuracy of a measurement can be improved by The accuracy of a measurement can be improved by taking several readings. The average reading is more taking several readings. The average reading is more accurate than a single reading.accurate than a single reading.

4.4. Zero error exists when the reading of the indicator of a Zero error exists when the reading of the indicator of a measuring instrument does not show zero. measuring instrument does not show zero. Measurements must be corrected for zero error.Measurements must be corrected for zero error.

Precision Precision

1.1. Precision is the difference in values Precision is the difference in values between several between several measurements obtained in measurements obtained in the same way.the same way.

2.2. Precision in measurement can be improved if a Precision in measurement can be improved if a more precise measuring instrument is used.more precise measuring instrument is used.

3.3. A micrometer screw gauge or a vernier calipers A micrometer screw gauge or a vernier calipers is more accurate compared to a ruler because is more accurate compared to a ruler because the divisions on its scale are smaller.the divisions on its scale are smaller.

Measuring with Vernier CalipersMeasuring with Vernier Calipers