KUULCHAT
SCIENCE MOCK
OBJECTIVE TEST
1.
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 = 40 g
Volume = 20 cm3
Density =
Density = 2 g cm-3
2.
The chemical symbol of potassium is
A.
K.
B.
N.
C.
P.
D.
S.
Answer: A
3.
Which of the following is at the centre of the solar system?
A.
Earth
B.
Mars
C.
Moon
D.
Sun
Answer: D
4.
An example of soil minor nutrient is
A.
calcium.
B.
iron.
C.
nitrogen.
D.
phosphorus.
Answer: B
5.
The joule is the S.I unit for
A.
energy.
B.
force.
C.
power.
D.
pressure
Answer: A
6.
The testis in mammals produces
A.
blood.
B.
lymph.
C.
sperms.
D.
urine.
Answer: C
7.
A ball is dropped from a height to the ground. The energy possessed by the ball just before it strikes the ground is called
A.
heat energy.
B.
kinetic energy.
C.
potential energy.
D.
sound energy.
Answer: B
Kinetic energy is the energy a body possesses by virtue of its motion.
8.
The part of the plant which is found in the soil is the
A.
flower
B.
stem
C.
leaf
D.
root
E.
fruit
Answer: D
9.
Which of the following is used by green plants for respiration?
A.
Carbon dioxide
B.
Oxygen
C.
Light
D.
Water
E.
Chlorophyll
Answer: B
10.
By the end of digestion, lean meat is turned into
A.
amino acids
B.
fatty acids
C.
glycerol
D.
glucose
E.
sugar
Answer: A
11.
In which of the following is urine produced?
A.
Bladder
B.
Kidney
C.
Liver
D.
Penis and vagina
E.
uterus
Answer: B
12.
An atom which contains more electrons than protons becomes a
A.
positive ion.
B.
negative ion.
C.
neutral atom.
D.
binary compound.
Answer: B
In a neutral atom, the number of protons balances that of electrons. Protons are positively charged and the electrons are negatively charged. When an atom gains more electrons, the negative charge becomes higher than the positive charge, hence the atom becomes a negative ion (Anion).
13.
The equation Carbon (IV) oxide + water Chlorophyll→Light Glucose + Oxygen, represents
A.
Breathing
B.
Diffusion
C.
Photosynthesis
D.
Respiration
E.
Transpiration
Answer: C
14.
Which of the following materials allows electric current to pass through easily?
A.
Aluminium
B.
Carbon
C.
Glass
D.
Water
Answer: A
15.
Which of the following pairs of diseases can be spread easily when food is exposed to houseflies?
A.
Cholera and Guinea Worm
B.
Dysentery and Malaria
C.
Dysentery and Guinea Worm
D.
Malaria and tuberculosis
E.
Dysentery and cholera
Answer: E
16.
Kerosine is able to reach the other end of a wick by
A.
diffusion.
B.
suction pressure.
C.
capillary action.
D.
osmosis.
Answer: C
17.
Boiling and chlorination are used in water purification to
A.
kill germs.
B.
help suspended particles to settle.
C.
remove suspended particles.
D.
remove hardness of the water.
Answer: A
18.
Which of the following associations between two organisms is always beneficial to both?
A.
Commensalism
B.
Mutualism
C.
Saprophytism
D.
Symbiosis
Answer: B
19.
Which of the following ions is formed by the loss of 2 electrons?
A.
Ca2+
B.
S2-
C.
K+
D.
F-
Answer: A
Cations are positively charged and they lose electrons. The number of positive charges in the superscript indicates the number of electrons lost. Calcium (Ca) has 2 positive charges which indicates the lost of 2 electrons.
20.
Which of the following forces tends to pull forces towards the centre of the earth?
A.
Electrostatic force
B.
Magnetic force
C.
Force of gravity
D.
Force of attraction
E.
Centrifugal force
Answer: E
21.
A beneficial effect of wind on the environment is
A.
promotion of photosynthesis in green plants.
B.
pollination in flowering plants.
C.
leaching in soils.
D.
erosion in soils.
Answer: B
22.
Which of the following is true about loamy soil?
I. Is formed from a mixture of sand and clay
II. It is good for plant cultivation
III. Its water retention is poor
A.
I only
B.
I and II only
C.
I and III only
D.
II and III only
E.
I, II and III
Answer: B
23.
When elements combine to form a compound the
A.
constituents can be separated by a physical process.
B.
volume of the compound is the sum of the volumes of the constituents.
C.
reaction does not involve a heat change.
D.
reaction can be represented by a chemical formula.
Answer: D
24.
An animal feed made up of high fibre is most likely to contain
A.
maize grain.
B.
silage.
C.
soybean.
D.
wheat grain.
Answer: B
25.
Leguminous crops such as beans may often be cultivated to
A.
Add humus to the soil
B.
Add nitrogen to the soil
C.
Add protein to the soil
D.
Make the soil loamy
E.
Increase the calcium content of the soil
Answer: B
26.
A mixture of alcohol and water can best be separated by
A.
filtration.
B.
condensation.
C.
distillation.
D.
evaporation.
Answer: C
Distillation is the process of separating the components of a liquid mixture through selective evaporation and condensation. The basis of separation is the difference in the vapor pressures (volatilities) of the respective components.
27.
Which of the following habits will help in the control of diseases contracted through air?
I. Not throwing human wastes into rivers
II. Washing of hands after visiting the toilet
III. Not spitting about in public places
IV. Keeping foods always covered
A.
I and II only
B.
II and III only
C.
III only
D.
I, II and IV only
Answer: B
28.
A piece of stone could be classified as an opaque material because it
A.
absorbs all the light incident on it.
B.
does not absorb light incident on it.
C.
allows all the light incident on it to pass through it.
D.
does not allow light incident on it to pass through it.
Answer: D
29.
The chemical formula H2 represents
A.
two atoms of hydrogen.
B.
two neutrons of hydrogen.
C.
two ions of hydrogen.
D.
two molecules of hydrogen.
Answer: A
30.
Which of the following explains why a wet cloth dries faster on a dry day than on a humid day?
A.
The rate of evaporation is very high during a dry day
B.
There is much water vapour in the atmosphere during a dry day
C.
It is very misty during a dry day
D.
there is no evaporation during a humid day
E.
The sun does not set during a humid day
Answer: A
31.
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
32.
Which of the following statements about friction is not true?
A.
It wears off materials
B.
It produces heat
C.
It opposes motion
D.
It increases speed
Answer: D
33.
A rigid bar which is capable of turning about a fixed point is a/an
A.
inclined plane.
B.
lever.
C.
screw.
D.
wheel and axle.
Answer: B
34.
Which of these instruments is used in measuring humidity?
A.
Hygrometer
B.
Thermometer
C.
Photometer
D.
Potometer
E.
Anemometer
Answer: A
35.
Which of the following substances can rust?
A.
Aluminium
B.
Bauxite
C.
Copper
D.
Steel
Answer: D
36.
When a stick is dipped into a pool of water, it appears to
A.
be longer than its length.
B.
ben away from the surface.
C.
be seen straight in the water.
D.
bend towards the surface.
Answer: D
37.
The chemical solution that can be used to test for the presence of protein in food substances is
A.
Benedict's solution.
B.
Fehling's solution.
C.
Iodine solution.
D.
Millon's reagent.
Answer: D
38.
Plants with thorns are not usually eaten by animals. The thorns therefore
A.
assist the plants to grow
B.
make the plant strong
C.
render the plant poisonous
D.
protect the plant
E.
make the plant unattractive
Answer: D
39.
Which of the following statements about the base of a transistor are correct? The base is
I. made very thin
II. made very wide
III. responsible for activating the transistor
IV. made of n-type semiconductor
A.
I and III only
B.
II and IV only
C.
I, III and IV only
D.
II, III and IV only
Answer: A
40.
In modern electrical wirings the colour code for the live wire is
A.
blue.
B.
brown.
C.
green.
D.
green and yellow.
Answer: B
THEORY QUESTIONS
1.
(a)
The diagrams below are illustrations of a set-up used to study the conditions for seed germination. The flasks are kept at 25 oC during the experiment. Study the diagrams carefully and answer the questions that follow.
(i)
What conclusion can be drawn from the results of flask 1 and flask 2?
(ii)
What conclusion can be drawn from the results of flask 2 and flask 3?
(iii)
The seedings in flask 2 died after two weeks. What can be the reasons for this occurrence?
(iv)
A candidate concluded that light was an important factor for the germination. Did the candidate make a correct conclusion?
(v)
Give a reason for the answer stated in (iv) and state which of the flasks in the experiment could be used to support your answer.
(b)
The diagram below are illustrations of an experimental set-up. Study the diagrams carefully and answer the questions that follow.
(i)
Name the measuring instrument that is in:
(α)
parallel;
(β)
series;
With the resistor R
(ii)
What quantity does each of the named instruments in (i) measure?
(iii)
Read and record the values as indicated on:
(α)
A in amperes;
(β)
V in volts.
(iv)
Use the values read in (iii) to calculate the value of R.
(v)
State one precaution to be taken in performing this experiment.
(c)
The diagrams below are illustrations of soil.Study the illustrations carefully and answer the questions that follow.
(i)
Identify each of the soil types labelled A, B and C
(ii)
Describe each of the soils under the following properties:
(α)
Particle size
(β)
Air space
(iii)
State two ways of improving soil type B for vegetable cultivation.
(d)
The diagrams below is a set-up for preparation of common salt in the laboratory. Study the diagrams carefully and answer the questions that follow.
(i)
Name each of the parts labelled IV, V and VI.
(ii)
Name two possible solutions that can react to product salt.
(iii)
Name the process that takes place when the two solution named in (ii) react.
(iv)
Name the process that takes place in the set-up B.
(v)
Write a balanced chemical equation for the reaction between the two solutions named in (ii).
(a)
(i)
Light is not necessary for germination
(ii)
Water is necessary for germination
(iii)
1. Lack of water/moisture
2. The food stored in the seed is used up/the seedlings cannot carry out photosynthesis/no sunlight
(iv)
No, light is not an important factor for germination
(v)
1. Because light is not necessary for the germination of seed.
2. The seed in flask 2 germinated even though the flask was lined with the aluminium foil
(b)
(i)
(α)
Voltmeter
(β)
Ammeter
(ii)
Voltmeter measures the potential difference/voltage and ammeter measures the current (electric)
(iii)
(α)
5 A
(β)
10 V
(iv)
Resistance = Voltage/Current = 10/5 = 2 Ω
(v)
Precautions
1. Voltmeter and ammeter must be of proper range/calibration
2. The key should be inserted only while taking readings
3. All the electrical connections must be tight
(c)
(i)
A = loamy soil/loam
B = sandy soil/sand
C = clayey soil/clay
(ii)
Description of soils
| Soil Type | Particle Size | Air space |
| A | Medium/large | Moderate |
| B | Large/medium | Large |
| C | Small | Small |
(iii)
Ways of improving sandy soil
1. Mulching the soil
2. Applying organic manure/compost/farm yard manure/fertilizer
3. Planting cover crops
(d)
(i)
IV = Evaporating dish
V = Retort/clamp stand
VI = Tripod stand
(ii)
Sodium hydroxide (NaOH) and hydrochloric acid (HCl)
(iii)
Neutralization
(iv)
Evaporation/boiling/heating
(v)
NaOH + HCl → NaCl + H20
2.
(a)
An atom has an atomic number of 8 and a mass number of 16. State the number of each of the following in the atom:
(i)
Protons
(ii)
Electrons
(iii)
Neutrons
(b)
(i)
Draw the structure of the atom in (a) above
(ii)
If the atom in (a) above gains two electrons what will be the charge of the ion?
(c)
State the end-product of the following food substances:
(i)
Carbohydrates
(ii)
Proteins
(iii)
Fats
(d)
(i)
What is the preservation of food?
(ii)
List four methods of food preservation.
Explain why one of the methods you have listed is used for food preservation.
(e)
(i)
An object is placed in front of a plane mirror. Draw a ray diagram to show how the image of the object is formed.
(ii)
State two characteristics of an image formed by a plane mirror.
(a)
Number of protons = Number of electrons = Atomic number
Atomic number = 8
An atom has an atomic number of 8 and a mass number of 16
(i)
Protons = 8
(ii)
Electrons = 8
(iii)
Mass number = Number of protons + Number of neutrons
Number of neutrons = Mass number - Number of protons
Mass number = 16
Number of neutrons = 16 - 8
Number of neutrons = 8
(b)
(i)
(ii)
The ion will have a charge of -2
(c)
End-product of food substances
(i)
Carbohydrates → Glucose
(ii)
Proteins → Amino acids
(iii)
Fats → Fatty acid and glycerol
(d)
(i)
Preservation of food is a way/process of preventing food from spoiling/decaying.
(ii)
Methods of food preservation
Boiling
Heat destroys/kills bacteria/germs already in the food.
Smoking
Water is taken out from the food/heat destroys/kills bacteria/germs already in the food.
Drying
Water is taken out from food. This prevents bacteria from acting on the food to cause decay
Frying
Water is taken from the food and this prevents decay.
Canning/Bottling
Food is heated/boiled to destroy/kill bacteria/germs present. Preservatives are added and sealed.
Freezing
Food is kept under a very low temperature which prevents bacteria/germs from acting or multiplying at that temperature.
Salting
Water is removed to prevent growth of bacteria.
(e)
(i)
(ii)
Characteristics of an image formed by a plane mirror
1. The image formed is laterally inverted
2. The image formed is virtual
3. The image formed is same size as the object
4. The image formed is upright/erect
5. Image distance from the mirror is the same as the object distance
3.
(a)
Draw and label a diagram to show how the eclipse of the sun is formed.
(b)
(i)
What is a lever?
(ii)
Classify the following as first class lever, second class lever or third class lever by copying and completing the table below:
Beam balance, crowbar, wheel barrow, a pair of scissors, claw hammer, sugar tong, human fore-arm and bottle opener
| First class lever | Second class lever | Third class lever |
(c)
(i)
What is pollination?
(ii)
Give two agents of pollination.
(d)
Name three excretory organs and the products they excrete.
(e)
(i)
What is an alloy?
(ii)
What are the compositions of each of the following alloys?
Bronze, Brass, Steel and Duralumin
(f)
Sodium chloride is prepared by the reaction between dilute hydrochloric acid and sodium hydroxide solution. Write down the equation for this reaction.
(a)
(b)
(i)
A lever is a simple machine which consists of a rigid bar/rod free to turn about a fixed turning point called the fulcrum/pivot.
(ii)
| First class lever | Second class lever | Third class lever |
|
Crowbar
|
Wheel barrow
|
Sugar tong
|
(c)
(i)
Pollination is the transfer of pollen grains from the anther of a flower to the stigma of the flower or another flower of the same species.
(ii)
Agents of pollination
1. Wind
2. Animal (Birds, Bats, Man)
3. Insect
4. Water/Rain
(d)
| Excretory Organs | Excretory Products |
| Skin | Sweat/water and salt/water and urea |
| Kidney | Urine/urea/water and salt |
| Lungs | Carbon dioxide/water vapour |
| Liver | Bile pigments |
(e)
(i)
An alloy is a uniform/homogeneous mixture of a metal and another metal or a non-metal.
(ii)
Compositions of alloys
Bronze → Copper and Tin
Brass → Copper and Zin
Steel → Iron and Carbon
Duralumin → Aluminium, Magnesium, Copper and Manganese
(f)
NaOH + HCl → NaCl + H2O
4.
a)
i)
What is a deficiency disease?
ii)
Give two deficiency diseases and their causes.
b)
i)
State the importance of excretion in living organisms.
ii)
Name two excretory organs of the human body and the substances they excrete.
c)
i)
Explain why gases are more compressible than solids.
ii)
Give two areas where the compressible nature of a gas is applied
d)
A piece of stone is dropped from a height to the ground.
State the energies possessed by the stone
i)
just before it was released from the maximum point;
ii)
midway between the fall;
ii)
just before it hit the ground.
a)
i)
Deficiency disease is a condition/disorder caused by the absence/lack/inadequate supply/inadequate intake of a particular nutrient/food substance.
ii)
Deficiency diseases associated with diet and their causes
| Disease | Cause |
| Rickets | Lack of vitamin D/calcium |
| Kwashiorkor | Lack of protein |
| Goitre | Lack of iodine |
| Night blindness | Lack of vitamin A |
| Scurvy | Lack of vitamin C (ascorbic acid) |
| Beriberi | Lack of vitamin B1 |
| Dermatitis | Lack of vitamin B2 |
| Pellagra | Lack of vitamin B3 |
| Marasmus | Lack of protein and carbohydrates |
| Anaemia | Lack of iron/folic acid |
| Prolonged bleeding | Lack of vitamin K |
| Infertility | Lack of vitamin E |
b)
i)
Importance of excretion in living organisms
1. If metabolic waste substances/products were not removed, they would be injurious/poisonous to the body
2. It removes waste products from the body
ii)
| Excretory organs | Excretory products |
| Skin | Sweat |
| Kidney | Urine |
| Lungs | Carbon dioxide, water vapour |
| Liver | Bile pigments/cholesterol |
c)
i)
Why gases are more compressible than solids
The particles/molecules of gases are far apart whereas in solids they are more compact.
ii)
Areas where the compressible nature of a gas is applied
1. Pumping of lorry tyres/football
2. Putting gas in bottled minerals
3. Blowing of balloons
4. Putting gas in bottles/gas cylinders
d)
i)
Potential energy
ii)
Potential energy and Kinetic energy
ii)
Kinetic energy
5.
(a)
(i)
Define pressure
(ii)
State three applications of pressure in everyday life
(b)
State four functions of the liver in digestion.
(c)
(i)
What is a compound?
(ii)
Give two properties of a compound
(iii)
Write down the name and the chemical formula of the compound formed between the following elements:
(α)
hydrogen and chlorine
(β)
magnesium and oxygen
(a)
(i)
Pressure is the force acting perpendicularly/normally over certain surface
OR
Pressure is the force acting perpendicularly/normally per unit area
Pressure (P) =
(ii)
Applications of pressure in everyday life
1. Opening a tin of milk with a nail
2. Braking system of a vehicle
3. Pumping bicycle/vehicle tyres with inflator
4. Using syrings to draw medicine
5. Pumping of water from a borehole
6. Hydraulic jack/press
7. Using straw
(b)
Functions of the liver in digestion
1. Removes excess glucose from the blood
2. Stores excess glucose as glycogen/animal starch
3. Converts glycogen to glucose (when glucose is needed)
4. Produces bile (which emulsifies fats and oils)
5. Removes toxins/toxic materials from the blood/purifies the blood
6. Stores blood
7. Lipid metabolism/breaks fat
8. Removes excess amino acids
(c)
(i)
Compound is a substance which contains two or more elements chemically combined.
(ii)
Properties of a compound
1. New substance formed with property different from any of the constituents
2. Substance formed cannot be broken down to obtain the reactants by any physical means
3. Compounds contain their constituents in one fixed proportion/composition/ratio
4. Their formation involves heat exchanges
(iii)
(α)
Compound formed when hydrogen and chlorine react
Hydrogen + Chloride → Hydrogen chloride (HCl)
H2(g) + Cl2(g) → 2HCl(g)
(β)
Compound formed when magnesium and oxygen react
Magnesium + Oxygen → Magnesium oxide (MgO)
2Mg + O2 → 2MgO
6.
a)
i)
What is a transistor?
ii)
Give two uses of a transistor.
b)
Mention the suitable solvent for each of the following solutes:
i)
grease;
ii)
ink stain;
iii)
starch;
iv)
cube sugar;
v)
oil paint;
vi)
iodine.
c)
i)
What is a respiratory organ?
ii)
Name two structures of the respiratory system of humans.
d)
i)
What is agricultural chain?
ii)
Name two types of agricultural chain.
a)
i)
A transistor is a three terminal (a base, emitter and collector) semiconductor device.
ii)
Uses of a transistor
1. Used as an amplifier
2. Used as a switch
3. Used as a rectifier
4. Used for tuning in radios
5. Used as a voltage/current regulator
b)
i)
Suitable solvents for grease
1. Petrol
2. Kerosene
3. Methylated spirit
ii)
Suitable solvents for ink stain
1. Milk
2. Alcohol
3. Parazone
4. Shaving cream
5. Kerosene
iii)
Suitable solvents for starch
1. Alcohol
2. Acetone
iv)
Suitable solvents for cube sugar
Water
v)
Suitable solvents for oil paint
1. Turpentine
2. Kerosene
3. Petrol
4. Thinner
vi)
Suitable solvents for iodine
1. Ethanol/Alcohol
2. Potassium iodide solution
c)
i)
Respiratory organ is an organ used by living organisms for gaseous exchange
ii)
Structures of the respiratory system of humans
1. Trachea
2. Lungs
3. Alveolus
4. Larynx
5. Diaphragm
6. Bronchus/Bronchi
7. Nostril/Nose
8. Nasal cavity
9. Intercostals muscle
10. Ribs
11. Pharynx
d)
i)
Agricultural chain is a series of stages that are connected in the production of agricultural goods/services.
ii)
Types of agricultural chain
1. Production
2. Processing
3. Supply
4. Value