Spectroscopy and Electromagnetic Spectrum Practice Test

Nitrogen is larger than oxygen thus making the 1s electrons easier to remove.

The effective nuclear charge on oxygen is greater than that of nitrogen.

Oxygen has more electrons and thus a greater amount of electron-electron repulsion present in the atom.

Nitrogen has 3 p-electrons and are thus unpaired leading to lower electron-electron repulsions.

There is a greater degree of electron shielding occurring in the oxygen 2p orbital.