When plants and animals decay,the organic nitrogen is converted into inorganic nitrogen. The inorganic nitrogen is in the form of

The gas $A$ has very low reactivity and reaches the stratosphere. It is non-toxic and non-flammable but is dissociated by $UV$ radiations in the stratosphere. The intermediates formed initially from the gas $A$ are:

Which of the following factors is responsible for water pollution?

How does the depletion of ozone layer occur by chlorofluorocarbons?

Explain the effects of acid rain on the Taj Mahal.

Water samples with $BOD$ values of $4 \ ppm$ and $18 \ ppm$ respectively are: