Atomic Structure - Result Question 74
####50. Energy of the state $S _1$ in units of the hydrogen atom ground state energy is
(2010)
(a) 0.75
(b) 1.50
(c) 2.25
(d) 4.50
Show Answer
Answer:
Correct Answer: 50. (a)
Solution:
- Ground state energy of electron in H-atom $\left(E _H\right)$
$$ E _H=\frac{k Z^{2}}{n^{2}}=k(Z=1, n=1) $$
For $S _1$ state of $Li^{2+}$,
$$ E=\frac{k(3)^{2}}{2^{2}}=\frac{9}{4} k=2.25 k $$
