NEETChemistryClassification of Elements and Periodicity in Properties
Why does oxygen have a smaller first ionization enthalpy compared to nitrogen?
Options
- AOxygen has more electrons.
- BOxygen has a smaller nucleus.
- COxygen has less shielding.
- DOxygen has greater electron-electron repulsion.
Correct answer
D. Oxygen has greater electron-electron repulsion.
Step-by-step solution
In the oxygen atom, two of the four 2p-electrons must occupy the same 2p-orbital, resulting in increased electron-electron repulsion, making it easier to remove an electron compared to nitrogen.