OnlineCBT
Chemistry · PYQ NEET UG 2024
हिन्दीArrange the following elements in increasing order of first ionization enthalpy: Li, Be, B, C, N Choose the correct answer from the options given below:
Correct answer · Option 4
\( \text{Li} < \text{B} < \text{Be} < \text{C} < \text{N} \)
Explanation
Be (\( 1s^2 2s^2 \)) has a stable fully filled s-subshell and higher penetration power than B (\( 1s^2 2s^2 2p^1 \)), so the first ionization enthalpy of Be is greater than that of B. The overall increasing order is \( \text{Li} < \text{B} < \text{Be} < \text{C} < \text{N} \).
