Which one of the three have the maximum number of carbon atoms in its molecule ? Justify your answer.

Question

The melting point of three members X, Y, and Z of a homologous series of hydrocarbons are -180°C, -140°C and -30°C respectively

Which one of the three have the maximum number of carbon atoms in its molecule ? Justify your answer. 

Answer 1

The homologue with maximum number of carbon atoms in its molecule has the highest melting point. Therefore, compound Z has the maximum number of carbon atoms in its molecules. It is clear from the given values of melting point in which 30°C is the highest of the three.