Major (Excess) CH CH NH CH I P -> P should be

primary amines react with excess methyl iodide to form quaternary ammonium salts. The nitrogen atom of primary amines contains a lone pair of electron. So, primary amines are strongly nucleophilic in nature. Moreover, the hydrogen atoms on nitrogen are easily replaceable. So, primary amines can act as nucleophiles and can react with alkyl halides. In the presence of excess alkyl halides, one amine molecule can repeatedly react with a number of alkyl halide molecules and result in the formation of a quaternary ammonium salt. The reaction is as follows : 2 3 3 3 RNH 3CH I RN CH I ->