Atoms And Nuclei Question 17
Question: Ionization potential of hydrogen atom is 13.6 V. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. The spectral lines emitted by hydrogen atoms according to Bohr’s theory will be [CPMT 1990; CBSE PMT 1996; MP PMT 1999; AMU (Med.) 2002]
Options:
A) One
B) Two
C) Three
D) Four
Show Answer
Answer:
Correct Answer: C
Solution:
Final energy of electron $ =-13.6+12.1=-1.51,eV. $ which is corresponds to third level i.e. $ n=3 $ . Hence number of spectral lines emitted $ =\frac{n(n-1)}{2}=\frac{3(3-1)}{2}=3 $