Nitrogen has the electronic configuration '1 s^2 2 s^2 p_x^1 2 p_y^1 2 p_z^1' and not '1 s^2 2 s^2 2 p_x^2 2 p_y^1 2 p_z^0' which is determined by

Explanation

i. The element .C. has a noble gas configuration, and-has a highest ionisatịon enthalpy.
ii. The element .B. has-three shell of electron present, large size and hence Iowest ionisation enthalpy.