What is the difference between two consecutive members in a homologous series of alkanes in terms of:
$(i)$ molecular mass.
$(ii)$ number of atoms of elements.

(N/A) In a homologous series of alkanes,each successive member differs from the previous one by a $-CH_2-$ group.
$(i)$ The difference in molecular mass is calculated as: $(1 \times 12) + (2 \times 1) = 14 \ u$.
$(ii)$ The difference in the number of atoms is one carbon atom and two hydrogen atoms,represented by the group $-CH_2-$.