Question

Question 1
i.
Choose the correct option.

a.
_______ is the study of the composition of matter, its structure, properties and the changes that it undergoes.

1. Biology

2. Mathematics

3. Chemistry

4. Geology

[1]
b.
Which of the following is NOT obtained from petroleum?

1. Petrol

2. Corundum

3. Wax

4. Kerosene

[1]
c.
The "lead" in pencil is made of _______ and clay minerals.

1. gypsum

2. sulphur

3. graphite

4. corundum



[1]
d.
Which of the following correctly represents the process of cellular respiration?

1. Carbon dioxide + Oxygen → Energy

2. Cell food + Carbon dioxide → Energy

3. Cell food + Oxygen → Energy + Carbon dioxide

4. Cell food + Energy → Oxygen + Carbon dioxide



[1]
e.
Which of the following statements is CORRECT?

1. Robert Boyle was the first to use indicators which change colour.

2. Dimitri Mendeleev put forward the atomic theory.

3. John Dalton is known for his work on periodic table.

4. All of these

[1]
ii.
State whether the following statements are true or false.

a.
DDT is a useful fertiliser.

[1]
b.
Nuclear energy is a renewable source of energy.

[1]
c.
Pure substances can be broken down physically into simpler substances.

[1]
d.
Liquids can flow.

[1]
e.
Boiling point of water is 100 degree Celsius.

[1]
Question 2
Answer the following.

i.
What is the composition of natural gas? Also mention why it is considered more valuable than other fossil fuels.

[3]
ii.
Explain how biogas is formed. Also mention its uses (any two).

[3]
iii.
Why do solids have a definite shape and volume?

[2]
iv.
If an object is taken to Mars from Earth, will there be a change in the mass or weight? Justify your answer.

[2]
Question 3
Answer the following.

i.
What are medicines? Suggest different ways in which medicines can be administered.

[3]
ii.
List any three applications of chemistry that help to conserve energy.

[3]
iii.
Study the diagram given below and answer the questions that follow:



a.
Which process does letter A represent?

[1]
b.
What happens to the energy of particles in process B?

[1]
c.
In process E, energy is absorbed or released?

[1]
d.
What happens to the motion of particles in process F?

[1]
Question 4
Give two examples of:

i.
Commonly used fertilisers.

[2]
ii.
Gemstones containing aluminium oxide.

[2]
iii.
Household consumer products.

[2]
iv.
Substances that exist in solid state at room temperature.

[2]
v.
Substances that exist in liquid state at room temperature.

Answer 1

Answer:

question number 1 is biology

Answer 2

Answer:

a) 3.Chemistry

b) 2.Corundum

c) 3. graphite

e) 1.

Explanation: