Question 2:

______ minerals include iron, aluminium, copper, tin, nickel, silver, gold and platinum etc.

Question 3:

Air gets polluted due to presence of pollutants in the _______ and it can result from both human and natural occurrences.

Question 4:

_____ occur when air gets polluted with sulphur dioxide and nitrogen oxide. Then they mix with water particles in the air to form a toxic substance. ________ lead to increased growth of algae, which leads to eutrophication.

Question 5:

Minerals such as _______ and ______ are important sources of energy. They are widely used in different sectors such as transport, agriculture and industry. 

Question 6:

____ is a good conductor of sound, we can hear speech or music or noise in the presence of _____.

Question 7:

Pollution from natural occurrences such as _____, _______, ______,  pollen dispersal, evaporation of organic compounds and natural radioactivity cause air pollution.

Question 8:

_______ acts as a universal solvent and gases such as oxygen, nitrogen, carbon dioxide and solids such as salts get readily dissolved with it.

Question 9:

Use of pesticides, fertilisers pollute the air by releasing harmful _______ into it.

Question 10:

________ minerals include sand, gravel, cement, salt, sulphur, phosphorous, diamonds and gems.