Question

First ionization enthalpy of nitrogen is higher than oxygen why

Answer 1

Because N has a half filled p subshell whereas O has 4 electrons in p subshell. Also half filled subshell is more stable and hence more energy is required to knock out electron from N and hence has more Ip

Answer 2

Answer:

(1) The electronic configuration of nitrogen (N, Z = 7) is 1s², 2s², 2p³ and that of oxygen (O, Z=8) is 1s², 2s² 2p^4.

(2) Nitrogen atom acquires extra stability due to half- filled 2p-orbitals while oxygen can acquire half-filled orbital and extra stability by losing one electron. Thus, oxygen can easily lose one electron.

(3) Nitrogen requires more energy to remove an electron due to extra stability. Therefore, first ionisation enthalpy of oxygen is less than that of nitrogen.