Question

(1)Fill in the blanks in the following sentences.​

(a) Coal is one of the ______ used to cook food.

(2)
Fill in the blanks in the following sentences.​

(b) When heated in air, coal burns and produces mainly ______ gas.

(3)
Fill in the blanks in the following sentences.​

(c) Coal tar is a black, thick ______ with an ______ smell.

(4)
Fill in the blanks in the following sentences.​

(d) Petroleum, ______ and ______ are fossil fuels.

(5)
Fill in the blanks in the following sentences.​

(e) Forests and coal are ______ natural resources.

Answer 1

(1)Coal is one of the fuels used to cook food. It was used earlier in railway​

engines to produce steam to run the​

engine. It is a fossil fuel.

(2)
When heated in air, coal burns and​

produces mainly carbon dioxide gas. It can be processed industrially to get the products such as coke, coal tar and coal gas.

(3)
Coal tar is a black, thick liquid with an unpleasant smell. It is a mixture of around 200 substances. It is one of the products obtained from coal.

(4)
The fossil fuels are formed from the dead remains of living organisms (fossils). Petroleum, coal and natural gas are fossil fuels.

(5)
Forests and coal are exhaustible natural resources. The resources present in limited quantity which ​

can be exhausted by human activities are called as exhaustible natural resources.