The process of covering water pipes made of Iron with

The chiefsource for the production of nitrogeneous fertilizers is : 

Which one of the following contributes largely to the greenhouse effect?

The mass number of a nucleus is

Chemical name of bleaching powder is

Brass is made of

Which of the following is used to increase the antiknocking property of petrol?

Which mineral is the ore Of aluminium?

Of the following which one pollutes the air of abig city? 

One property of ammonia is 

Burning pyrites ore gives out