Amongst the following, the total number of species NOT having eight electrons around central atom in its…

Among the given species ${\mathrm{NH}}_3$ and ${\mathrm{CCl}}_4$ is having eight electrons at the central atoms. In ammonia, one lone pair and three bond pairs at nitrogen. In carbon tetrachloride four bond pairs are present.

In ${\mathrm{AlCl}}_3$, aluminium has three bond pairs, i.e., it has incomplete octet.

In ${\mathrm{BeCl}}_2$, beryllium has two bond pairs, i.e., it has incomplete octet.

In ${\mathrm{PCl}}_5$, phosphorus has five bond pairs, i.e, it has expanded octet.