KUULCHAT
SCIENCE MOCK

OBJECTIVE TEST

1.

The force that binds molecules of the same substances together is called

A.

adhesion.

B.

cohesion.

C.

capillary action.

D.

surface tension.

Answer: B

Difference between adhesive and cohesive force

Cohesive force is the force that attracts molecules of the same substance while Adhesive force is the force that binds molecules of different substances together.

Why water wets glass

Water wets glass and spreads out on it because the adhesive forces between the liquid and the glass are stronger than the cohesive forces within the water.

2.

Which of the following substances is a compound?

A.

Copper

B.

Diamond

C.

Sucrose

D.

Sulphur

Answer: C

Copper and sulphur are elements. Diamond is made up of only carbon elements so can't be classified as a compound because compounds are made up of two or more different elements.

Sucrose (C12H22O11) is simply the chemical name for sugar and is a compound that consists of various elements i.e. carbon, hydrogen, and oxygen that combine chemically in a definite ratio.

3.

Which of the following step(s) is/are required in the scientific method?

I. Formulation of hypothesis

II. Identification of the problem

III. Experimentation

A.

I only

B.

II only

C.

II and III only

D.

I, II and III

Answer: D

4.

Which of the following is the percentage composition of oxygen in the air?

A.

0.03

B.

1

C.

21

D.

78

E.
98

Answer: C

5.

An atom of an element is represented as 1327   X. How many neutrons are in the nucleus of the atom?

A.

13

B.

14

C.

27

D.

40

Answer: B

The superscript represents the mass number which is made up of neutrons and protons

The value of the superscript is 27.

Number of protons + Number of neutrons = 27

The subscript represents the atomic number which is the number of electrons in a neutral atom. In a neutral atom, the number of electrons is equal to the number of protons.

Atomic number = 13
Atomic number = Number of electrons
Number of electrons = Number of protons

Number of electrons = 13
Number of protons = 13

Protons + Neutrons = 27
13 + Neutrons = 27
Neutrons = 27 - 13
Neutrons = 14

6.

A balanced diet is one which is made up of

A.

right proportions of protein, carbohydrates and oil.

B.

equal amounts of protein, carbohydrates and oil.

C.

enough water and iodated salt.

D.

vegetables, fruits and water.

Answer: A

7.

A stone displaced 20 cm3 of water when immersed in the water. If the mass of the stone is 40 g. find the density of the stone

A.

60 g cm-3

B.

40 g cm-3

C.

2 g cm-3

D.

0.5 g cm-3

Answer: C

Density

Density = Mass Volume

Mass = 40 g
Volume = 20 cm3

Density = 40 g 20  cm3

Density = 2 g cm-3

8.

Which of the following instruments is connected in parallel across a resistor in an electrical circuit?

A.

Ammeter

B.

Voltmeter

C.

Ohmmeter

D.

Galvanometer

Answer: B

Voltmeter: is used to measure the potential difference between two points in an electrical circuit and its connected in parallel in an electric circuit

Ammeter: is used to measure the electric current in an electric circuit and it is connected in series in an electric circuit

Galvanometer: is used to detect the presence of small electric current and voltage and its connected in series

Ohmmeter: is used to measure the electrical resistance

9.

Which of the following states of matter are fluids

I. Solid

II. Liquid

III. Gas

A.

I and II only

B.

I and III only

C.

II and III only

D.

I, II and III

Answer: C

A fluid is matter that flows when a force is applied to it. All gases and all liquids are fluids.

10.

An example of a crop that reduces the fertility of the soil rapidly is

A.

Beans

B.

Legumes

C.

Groundnuts

D.

Cassava

E.
Plantain

Answer: D

11.

How many days does the moon take to go round the earth.

A.

31

B.

30

C.

29

D.

27

Answer: C

12.

One best way of making water safe for drinking is by

A.

adding washing soda.

B.

filtering.

C.

adding common salt.

D.

boiling.

Answer: D

13.

The systematic name of the compound FeS is

A.

iron (I) sulphide.

B.

iron (II) sulphide.

C.

iron (III) sulphide.

D.

iron (IV) sulphide

Answer: B

14.

In humans, features of parents are passed on to offspring through

A.

breastfeeding.

B.

reproduction.

C.

good training.

D.

sharing the same things.

Answer: B

15.

Which of the following statements about acids correct

I. They react with the calcium carbonate to give a gas

II. They turn red litmus paper blue

III. They react with reactive metals to give a gas

IV. They turn blue litmus paper red

A.

I, II and IV only

B.

I, II and III only

C.

II, III and IV only

D.

D. I, III and IV

Answer: D

An acid is a substance that donates protons (in the Brønsted-Lowry definition) or accepts a pair of valence electrons to form a bond (in the Lewis definition). acid, any substance that in water solution tastes sour, changes the color of certain indicators (e.g., reddens blue litmus paper), reacts with some metals (e.g., iron) to liberate hydrogen, reacts with bases to form salts, They react with the calcium carbonate to give a gas and promotes certain chemical reactions (acid catalysis).

16.

The force which tends to pull an object in a circular motion towards the centre of the circle is called

A.

centripetal force.

B.

electrostatic force.

C.

gravitational force.

D.

magnetic force.

Answer: A

17.

Which of the following elements is a liquid at room temperature.

A.

Carbon.

B.

Mercury.

C.

Silver.

D.

Sulphur.

Answer: B

18.

A torchlight derives its energy from

A.

petrol

B.

kerosene

C.

a magnet

D.

gas oil

E.
a dry cell

Answer: E

19.

Some plants shed their leaves during the dry season to prevent

A.

water loss.

B.

heat loss.

C.

catching fire.

D.

losing nutrients.

Answer: A

20.

The atom of an element has 4 protons and 5 neutrons in its nucleus. How many shells are occupied in the atom?

A.

1

B.

2

C.

3

D.

4

E.

5

Answer: B

The number of protons equals the number of electrons in a neutral atom.

Since there are 4 protons, the number of electrons is also 4

The first shell of an atom takes a maximum of 2 electrons and the subsequent shells take maximum of 8 electrons

For 4 electrons, the first shell will take 2 electrons and the second shell will take the remaining 2 electrons.

Hence the atom has 2 shells.

21.

The bad smell that comes out of a urinal is due to the presence of

A.

ammonia.

B.

hydrogen.

C.

carbon dioxide.

D.

nitrogen.

Answer: A

Ammonia has a very strong odor that is irritating.

22.

Soil acidity can be reduced by adding

A.

acid solution

B.

ammonium sulphate

C.

fertilizer

D.

lime

E.
rotten leaves

Answer: D

23.

When a thermometer is put in hot water, the mercury level rises because the mercury increases in

A.

density.

B.

mass.

C.

volume.

D.

weight.

Answer: C

The mercury expands and the volume increases.

24.

Which of the following is not a mammal?

A.

Whale

B.

Bat

C.

Cat

D.

Hen

E.
Mouse

Answer: D

25.

Which of the following human activities pollutes the environment?

I. Release of cement dust into the atmosphere
II. Dumping of refuse into water bodies
III. Burning of rubbish

A.

I and II only

B.

II and III only

C.

I and III only

D.

I, II and III

Answer: D

26.

Which of the following statement(s) about pressure in fluids is/are correct? Pressure

I. decreases with depth

II. increases with depth

III. does not depend on the area

A.

I only

B.

II only

C.

I and II only

D.

II and III only

Answer: B

The pressure in a liquid is different at different depths. Pressure increases as the depth increases. The pressure in a liquid is due to the weight of the column of water above. Since the particles in a liquid are tightly packed, this pressure acts in all directions. For example, the pressure acting on a dam at the bottom of a reservoir is greater than the pressure acting near the top. This is why dam walls are usually wedge-shaped. The greater pressure at the bottom would give a greater ‘force per unit area’ on the wall.

27.

Dehusking and shelling are both activities carried out in the processing of

A.

cowpea.

B.

groundnut.

C.

maize.

D.

sorghum.

Answer: C

28.

The function of the platelets in the circulatory system of humans is to

A.

Transport oxygen

B.

Transport carbon dioxide

C.

Clot of blood

D.

Defend the blood

Answer: C

29.

Plants are different from animals because they

A.

have protoplasm

B.

have chlorophyll

C.

are able to respire

D.

are able to reproduce sexually

Answer: B

30.

The edible part of the mango fruit is called

A.

endocarp

B.

drupe

C.

fibre

D.

mesocarp

E.
epicarp

Answer: D

31.

Which of the following natural cycles directly involves the sun?

I. Carbon cycle
II. Water cycle
III. Nitrogen cycle

A.

I, II and III

B.

I and II only

C.

II and III only

D.

I only

Answer: B

32.

The pressure in fluids

A.

increase with depth.

B.

decrease with depth.

C.

acts upwards at any point.

D.

acts differently in all directions.

Answer: A

33.

A fuse is used in an electrical circuit to

A.

measure the energy used up.

B.

protect appliances.

C.

provide more current.

D.

make sure current flows continuously.

Answer: B

A fuse is an electrical safety device that operates to provide overcurrent protection of an electrical circuit. It is designed to melt and separate in the event of excessive current thereby stopping or interrupting the current.

34.

Washing down of soil nutrients beyond the reach of roots of plants is referred to as

A.

aeration.

B.

infiltration.

C.

leaching.

D.

percolation.

Answer: C

35.

The insect responsible for the spread of malaria is the

A.

female anopheles mosquito.

B.

housefly.

C.

male anopheles mosquito

D.

tsetse fly.

Answer: A

Why the male mosquitoes cannot transmit malaria

The biting female Anopheles mosquito may carry malaria. Male mosquitoes do not bite so cannot transmit malaria or other diseases. The adult females are generally short-lived, with only a small proportion living long enough (more than 10 days in tropical regions) to transmit malaria.

36.

Which of the following substances is added to the soil to reduce its acidity?

A.

Charcoal

B.

Humus

C.

Lime

D.

Manure

Answer: C

Lime is a base, hence neutralizes the acid in the soil.

37.

Which of the following statements about pressure in liquids is/are correct?

I. Pressure in liquids at the same level acts equally in all directions.

II. Pressure in liquids depend on the area of the liquid.

III. Pressure in liquids decreases with depth.

A.

I only

B.

II only

C.

I and III only

D.

I, II and III

Answer: A

Pascal's law states that pressure in liquids is transmitted equally in all directions.

Pressure in liquids does not depend on the surface area.

The pressure exerted by a liquid increases with depth.

38.

The type of cloud that gives rain is

A.

cumulus.

B.

cirrus.

C.

nimbus.

D.

stratus.

Answer: D

39.

In which of the following circuit diagrams below will the bulb light?

A.

B.

C.

D.

Answer: B

Positive part must be connected to the negative part and negative to positive.

40.

A group of stars found in the universe is called

A.

galaxy.

B.

meteor.

C.

meteorite.

D.

planet.

E.

solar system.

Answer: A

THEORY QUESTIONS

1.

(a)

(i)

Name the gas which is used in both rusting and burning

(ii)

State two ways in which rusting can be prevented in everyday life.

(b)

Classify each of the following items as element, compound, mixture or colloid:

(i)

Sodium chloride

(ii)

Sugar solution

(iii)

Fog

(iv)

Hydrogen

(v)

Sulphur

(c)

(i)

Use any three of the following to form a food chain:

Man, bird, green grass, goat, grasshopper

(ii)

Name two diseases that can be controlled by immunization.

(d)

(i)

A boy throws a stone vertically up into the air. What are the energy changes that take place as the stone falls to the ground?

(ii)

Give two appliances which use electromagnets in their operation

(iii)

List two ways in which a magnet can lose its magnetism.

(a)

(i)

The gas which is used in both rusting and burning is oxygen

(ii)

Ways in which rusting can be prevented in everyday life

1. Painting
2. Galvanizing (electroplating)
3. Greasing
4. Oiling
5. Alloying

(b)

Element Compound Mixture Colloid

Sulphur
Hydrogen

Sodium chloride

Sugar solution

Fog

(c)

(i)

Green grass → grasshopper → bird

OR

Green grass → goat → man

(ii)

Diseases that can be controlled by immunization

1. Tuberculosis
2. Measles
3. Poliomyelitis
4. Whooping cough
5. Diphtheria
6. Tetanus
7. Yellow fever
8. Cholera

(d)

(i)

Potential energy → Kinetic energy → Sound energy → Heat energy

(ii)

Appliances which use electromagnets in their operation

1. Telephone receivers
2. Loudspeakers
3. Electric bells
4. Burglar alarms
5. Microphones

(iii)

Ways in which a magnet can lose its magnetism

1. Heating the magnet in fire
2. Striking the magnet continuously with a hammer
3. Placing it in a solenoid through which an alternating current flows

2.

(a)

A sample of garden soil is put in a cylinder containing water. It is shaken and allowed to settle.

Draw and label the layers formed.

(b)

(i)

Name four types of forces.

(ii)

A boy used a catapult to pluck a mango from a tree. State two forces involved in this activity.

(iii)

Where are the forces in (b) (ii) applied?

(c)

Describe an experiment to show that there is change in heat energy when a new substance is formed.

(a)

(b)

(i)

Types of forces

1. Force of gravity
2. Weight
3. Magnetic force
4. Electrostatic force
5. Frictional force
6. Centripetal force
7. Viscous force
8. Tensional/Elastic force
9. Adhesion
10. Cohesion
11. Centrifugal force

(ii)

1. Tensional/Elastic force
2. Force of gravity
3. Frictional force

(iii)

1. Tension/elastic force in the rubber band of the catapult pushed the stone
2. Force of gravity brought down the mango
3. Frictional force acts between the stone and the mango/between the leather of the catapult and the stone/between the palm and the stick of the catapult

(c)

Experiment to show that there is change in heat energy when a new substance is formed

1. Take two solutions/substances such as lead nitrate/lead (II) trioxonitrate (V) and dilute hydrochloric acid
2. Measure the temperature of the separate solutions and record
3. Pour the acid into the nitrate
4. Measure the temperature as you stir gently
5. It will be observed that a new substance is formed with a change in temperature
6. It can therefore be concluded that there is a change in heat energy when a new substance is formed

3.

a)

i)

What is a simple machine?

ii)

Give two examples of a simple machine?

b)

i)

What is rusting?

ii)

State two effects of rusting.

c)

i)

What are food nutrients?

ii)

Classify the following food items as carbohydrate, fats and oil or protein:

Beans, palm fruits, meat, margarine, bread and maize.

d)

i)

State two effects of malnutrition in farm animals.

ii)

Mention one disease of farm animals caused by virus.

a)

i)

Simple machine is a device that makes work easier/faster.

OR

Simple machine a device which enables a small force (effort) to overcome a large force (load).

ii)

Examples of a simple machine

1. Lever (Examples are a crowbar, claw hammer, a pair of pliers)
2. Wheel and axle (Examples are the steering wheel of a car, bicycle pedal)
3. Pulley (Examples are a pulley used in raising a load)
4. The inclined plane (Examples are ramps, staircases, hilly roads)
5. The wedge (Examples are knife, axe, plough)
6. Screw (Examples are A screw bolt)

b)

i)

Rusting is the reaction of iron or iron containing substances with water/moisture and air/oxygen to form an oxide of iron.

ii)

Effects of rusting

1. It causes iron to lose its strength/structure resulting in accident
2. It can cause collapse of building and bridges resulting in maintenance cost
3. It causes iron to lose its lustre

c)

i)

Food nutrients are substances which when taken in by living things help in performing of life activities

OR

Food nutrients are essential materials/substances present in food which when taken in by living things help in performing of life activities

ii)

Carbohydrate → Bread, maize
Fats and oil → Palm fruits, margarine
Protein → Beans, meat

d)

i)

Effects of malnutrition in farm animals

1. Loss of weight/stunted growth
2. General body weakness
3. Reduced activity
4. Dullness
5. Less resistant to diseases
6. Reduced reproduction
7. Poor formation of bones

ii)

Viral diseases of farm animals

1. Rinder-pest
2. Newcastle
3. Gumboro
4. Fowl pox
5. Cow pox
6. Marek's disease
7. Swine fever
8. Bird flu
9. Foot and mouth disease

4.

a)

i)

What is fertilization

ii)

Describe briefly the processes that lead to fertilization in humans after mating.

b)

i)

Define the term density

ii)

Describe briefly how the density of a piece of stone could be determined

c)

i)

What is an element?

ii)

Classify each of the following substances as an element, compound or mixture: Water, air, potassium, alcohol, common salt, sugar

a)

i)

Fertilization is the fusion of the male and female sex cells to form a zygote.

ii)

The processes that lead to fertilization in humans after mating

1. The sperms move through the vagina, cervix and uterus to the fallopian tube
2. Only one of the millions of sperms succeeds to penetrate the membrane of the ovum
3. The nuclei of the sperm and ovum unit/fuse to form a zygote

b)

i)

Density of a substance is the mass per unit volume of the substance.

OR

Density = Mass (M) Volume (V)

ii)

Determination of the density of a stone

1. Measure/weigh the mass of stone by means of a beam/chemical balance as M g
2. Fill a large measuring cylinder with water to a suitable level and record the volume as V1 cm3
3. Tie the stone with thread and gently lower it into the water in the measuring cylinder and record the new volume as V2 cm3

The density of the stone is then calculated as follows:

Volume of stone = V2 cm3 - V1 cm3

Mass of stone = M g

Density = Mass Volume

Density of the stone = M g (V2 - V1)cm3

c)

i)

An element is a substance that cannot be broken down/split into simpler substances by any known chemical means.

ii)

Element Compound Mixture
Potassium

Water
Common salt
Alcohol
Sugar

Air
5.

(a)

(i)

Explain vegetative reproduction

(ii)

State two differences between sexual reproduction and vegetative reproduction.

(iii)

Give one advantage of vegetative reproduction.

(b)

(i)

Name suitable solvents for the following substances:

oil paint, fat, common salt, plant pigments.

(ii)

What is the name given to a substance dissolved by a solvent?

(c)

The diagram below represent a simple machine.

(i)

What class of simple machine does it represent?

(ii)

Name the parts labelled I, II and III

(iii)

Give two examples of machines used in everyday life which work on the same principle as the system illustrate above.

(a)

(i)

Vegetative reproduction is the propagation of new individuals of a particular species by means of parts of a parent plant other than (fertilized) seeds.

OR

Vegetative reproduction is a form of reproduction whereby plants reproduce young ones from growing parts or buds of the parent plant.

(ii)

Differences between sexual reproduction and vegetative reproduction

Sexual Reproduction Vegetative Reproduction
Gives rise to variables (in species) Give rise to same species/no variation
Involves male and female sex cells/gametes or seeds Involves only one plant/leaves/stem/root

(iii)

Advantages of vegetative reproduction

1. Results in species of the same characteristics/features
2. Stores enough food reserve for the offspring
3. Growth is more rapid/fast
4. Only one parent is required to produce the offspring/does not require any agent as in pollination

(b)

(i)

Substance Solvent
Oil paint Turpentine/Petrol/Kerosene/Thinner
Fat Petrol/Carbon textrachloride
Common salt Water
Plant pigment Alcohol/acetone

(ii)

Solute

(c)

(i)

Second class lever

(ii)

I → Effort
II → Load
III → Pivot/Fulcrum

(iii)

Examples of second class levers

1. Wheelbarrow
2. Bottle opener
3. Nutcracker
4. Staplers
5. Nail clippers
6. Doors or gates

6.

a)

i)

What is a magnetic field?

ii)

Name two methods of making magnets.

b)

Explain briefly the term teenage pregnancy.

c)

Write the formula for each of the following compounds:

i)

calcium chloride;

ii)

copper (I) oxide;

iii)

nitrogen (IV) oxide;

iv)

ammonia.

d)

i)

List three physical properties of soil.

ii)

What is the texture of clayey soil?

a)

i)

Magnetic field is a region/area around a magnet/moving electric charge within which the force of magnetism acts/can be felt/experienced

ii)

Methods of making magnets

1. By induction
2. By stroking
3. By the use of electricity
4. By hammering/hitting

b)

Teenage Pregnancy

When a girl under the age of 20 conceives/takes seed or when a female/girl under the age of 20 gets pregnant

c)

i)

calcium chloride → CaCl2

ii)

copper (I) oxide → Cu2O

iii)

nitrogen (IV) oxide → NO2

iv)

ammonia → NH3

d)

i)

Physical properties of soil

1. Texture
2. Structure
3. Temperature
4. Colour
5. Permeability
6. Water
7. Capillarity
8. Organism
9. Drainage
10. Air
11. Strength/consistence
12. Porosity

ii)

Texture of clayey soil

It is smooth/slippery/sticky when wet