What is the product formed when aniline reacts with one mole of chloromethane?

N-Methylaniline

The correct answer is option 1. N-Methylaniline.

When aniline \((C_6H_5NH_2)\) reacts with one mole of chloromethane \((CH_3Cl)\), a nucleophilic substitution reaction occurs, where the chlorine atom in chloromethane is substituted by the amino group in aniline. This reaction is known as the alkylation of aniline.

The reaction proceeds as follows:

The product formed is N-methylaniline \((C_6H_5NHCH_3)\), where the methyl group from chloromethane is attached to the nitrogen atom of the aniline molecule.

Therefore, the correct answer is N-Methylaniline.