Amongst the following elements whose electronic configurations are given below, the one having the highest ionisation enthalpy is

Amongst the following elements whose electronic configurations are giv

1.	Amongst the following elements whose electronic configurations are given below, the one having the highest ionisation enthalpy is
Answer» [Ne] `3s^(2) 2p^(1)` [Ne] `3s^(2) 3P^(3)` [Ne]`3s^(2) 3p^(2)` [Ar]`3D^(10) 4s^(2) 4p^(3)` Solution :[Ne] `3s^(2) 3p^(3)` In the electronic configuration of (B) and (D) half-filled 3p orbitals (B) represents PHOSPHORUS and (Q represents arsenic but (B) is smaller in size than (D) So, (B) has highest ionisation enthalpy. Ionisation enthalpy increases left to RIGHT in the periodic table as the size decreases.