The presence of soluble fluoride ion up to $1 \ ppm$ concentration in drinking water is:

The molecule that has minimum or no role in the formation of photochemical smog is

Which of the following is an air pollutant?

$A$ large number of fish are suddenly found floating dead on a lake. There is no evidence of toxic dumping,but you find an abundance of phytoplankton. Suggest a reason for the fish kill.

Which of the following practices will not come under green chemistry?

Noosphere is a synonym of