

$(i)$ ${C_6}{H_5}{N^ + } \equiv NC{l^ - }$ $(ii)$ ${C_6}{H_5}{N^ + } \equiv N$
$(iii)$ ${{\overset{\centerdot }{\mathop{C}}\,}_{6}}{{H}_{5}}$ $(iv)$ $C_6H_5Cl$
$(I)$ $CH_2 = CH - C \equiv CH$
$(II)$ $CH \equiv C - C\equiv CH$
$(III)$ $CH_3 - CH = CH_2$
$(IV) $ $CH_2 = CH - C = CH_2$