Atoms And Nuclei Question 123
Question: The frequency of 1st line of Balmer series in $ H_{2} $ atom is $ {\nu_{0}} $ . The frequency of line emitted by singly ionised He atom is [CPMT 2002]
Options:
A) $ 2{\nu_{0}} $
B) $ 4{\nu_{0}} $
C) $ {\nu_{0}}/2 $
D) $ {\nu_{0}}/4 $
Show Answer
Answer:
Correct Answer: B
Solution:
$ \nu \propto Z^{2}\Rightarrow \frac{{\nu_{H_{2}}}}{{\nu_{He}}}={{( \frac{1}{2} )}^{2}}=\frac{1}{4}\Rightarrow {\nu_{He}}=4{\nu_{H_{2}}} $ = 4n0
