JEE MainChemistryClassification of Elements and Periodicity in Properties
Which of the following ground-state electronic configurations represents the element with the highest first ionization enthalpy?
Options
- A[He] 2s^2 2p^2
- B[Ne] 3s^2 3p^2
- C[Ne] 3s^2 3p^3
- D[He] 2s^2 2p^3
Correct answer
D. [He] 2s^2 2p^3
Step-by-step solution
The first ionization enthalpy generally increases across a period from left to right and decreases down a group. The given configurations correspond to: [He] 2s^2 2p^2 : Carbon (Period 2, Group 14) [Ne] 3s^2 3p^2 : Silicon (Period 3, Group 14) [Ne] 3s^2 3p^3 : Phosphorus (Period 3, Group 15) [He] 2s^2 2p^3 : Nitrogen (Period 2, Group 15) Elements in Period 2 have higher ionization enthalpies than those in Period 3 due to their smaller atomic size. Between Carbon and Nitrogen, Nitrogen has a higher effective nuclear