Atomic Structure - Result Question 72
####48. Statement I The first ionisation energy of Be is greater than that of B.
Statement II $2 p$-orbital is lower in energy than $2 s$.
(2000)
Passage Based Questions
The hydrogen-like species $Li^{2+}$ is in a spherically symmetric state $S _1$ with one radial node. Upon absorbing light the ion undergoes transition to a state $S _2$. The state $S _2$ has one radial node and its energy is equal to the ground state energy of the hydrogen atom.
Show Answer
Answer:
Correct Answer: 48. (b,d)
Solution:
- Assertion is correct $\operatorname{Be}\left(1 s^{2}, 2 s^{2}\right)$ has stable electronic configuration, removing an electron require more energy than the same for $B\left(2 p^{1}\right)$. Reason is incorrect (Aufbau principle).
