Name the substance which gives heat and light after combustion.

2

(a)

Which type of substances are called combustible substances?

2

(a)

What do you mean by deforestation?

2

(a)

Why should we take special care in storing kerosene oil?

2

(a)

What are the different zones of a candle flame?

2

(a)

Give one disadvantage of burning a fuel in insufficient supply of air.

2

(a)

What do you understand by fuel efficiency?

2

(a)

State one different way by which fire can be extinguished?

2

(a)

Boojho: We have read that the sun produces heat and light. Is that through a combustion process?
Paheli: How can it be? There is no air in the sun.

2

(a)

Why are we advised never to sleep in a room with burning coal fire in it?

2

(a)

What are the characteristics of an ideal fuel?

2

(a)

When the clothes of a person catch fire the person is covered with a blanket to extinguish fire. Why?

2

(a)

When kerosene oil is heated a little, it will catch fire. But when wood is heated a little, it does not catch fire. Why?

2

(a)

Name two substances that burn with flame and without flame?

2

(a)

How does fire brigade work to extinguish fire?

2

(a)