Periodic Table — Easy JEE chemistry MCQ
**[JEE Mains 2026]** What is the correct order of first ionization enthalpy?
- A. B > Be > Li > Na
- B. Be > B > Li > Na
- C. Na > Li > B > Be
- D. Li > Na > B > Be
Solution
Ionization enthalpy generally increases across a period and decreases down a group.
Be > B (anomaly: Be has full 2s², B loses 2p electron more easily).
B > Li (same period, B is to the right).
Li > Na (same group, Li is above Na).
Order: Be > B > Li > Na.