The chief source of naphthalene is
The chiefsource for the production of nitrogeneous fertilizers is :
The most abundant constituent of atmospheric air is
Chemical name of bleaching powder is
“Firefighting clothes” are made from
The particle required to continue the chain process of Uranium fission is:
Of the following which one pollutes the air of abig city?
Water gas is the mixture of
Mercury is a :
Urea is a —
