(આપેલ : આણ્વિય દળો : $C$ : $12.0\, u$, $H : 1.0\, u , N : 14.0\, u , Br : 80.0\, u ]$
${C_2}{H_5}N{H_2}\,\xrightarrow{{HN{O_2}}}a$
${C_2}{H_5}N{H_2}\,\xrightarrow{{{C_6}{H_5}CHO}}b$
${C_2}{H_5}N{H_2}\,\xrightarrow{{NOCl}}c$
${C_2}{H_5}N{H_2}\,\xrightarrow{{{C_6}{H_5}S{O_2}Cl}}d$