Atomic Structure Question 487
Question: A hydrogen atom in the ground state is excited by monochromatic radiation of wavelength $ \lambda \overset{o}{\mathop{A}}, $ . The resulting spectrum consists of maximum 15 different lines. What is the wavelength $ \lambda $ -
Options:
A) $ 937.3,\overset{o}{\mathop{A}}, $
B) $ 1025,\overset{o}{\mathop{A}}, $
C) $ 1236,\overset{o}{\mathop{A}}, $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
- Total number of spectral lines given by
$ \frac{1}{2}[n-1]\times n=15 $ ;
$ \therefore ,n=16 $ Thus, electron is excited upto 6th energy level from ground state. Therefore, $ \frac{1}{\lambda }=R_{H}[ \frac{1}{1^{2}}-\frac{1}{n^{2}} ]=109737\times \frac{35}{36} $ ; $ \lambda =9.373\times {10^{-6}},cm=937.3,\overset{o}{\mathop{A}}, $
