Chemistry - CHEMICAL BONDING Question with Solution | TestHub

Find the number of species which do not exist in ordinary condition : ${\mathrm{NH}}_4^{+},{\mathrm{SF}}_6,{\mathrm{OF}}_4,{\mathrm{S}}_2,{\mathrm{P}}_2,{\mathrm{SiO}}_2,{\mathrm{BeCl}}_4^{-2},{\mathrm{NCl}}_5,{\mathrm{AlF}}_6^{-3},{\mathrm{CF}}_6^{-2}$