In \(NF _{3}, SF _{4}, ClF _{3}\) central atom (i.e. \(\left. N , S , Cl \right)\) having lone pair therefore act as lewis base.
In \(PCl _{5}\) central atom \((P)\) does not have lone pair therefore does not act as lewis base.
(for $AgCl$ માટે $K_{sp}$ $= 1.8 \times 10^{-10},$ for $PbCl_2$ માટે $ K_{sp}$ $= 1.7 \times 10^{-5}$)