Assertion (A): In a homologous series of alcohols, the formula for the second member is C₂H₅OH and the third member is C₃H₇OH.

Reason (R): The difference between the molecular masses of the two consecutive members of a homologous series is 144.

In an ecosystem, 10% of energy available for transfer from the trophic level to the next is in the form of:

Soil fertility is determined by its ability to:

Assertion (A): In the process of nuclear fission, the amount of nuclear energy generated by the fission of an atom of uranium is so tremendous that it produces 10 million times the energy produced by the combustion of an atom of carbon from coal.

Reason (R): The nucleus of a heavy atom such as uranium, when bombarded with low energy neutrons splits apart into lighter nuclei. The mass difference between the original nucleus and the product nuclei gets converted to tremendous energy.

What is ‘rusting ‘? Describe with a labelled diagram an activity to investigate the conditions under which iron rusts.