Question

For the following allowed transitions, which photon would have the largest wavelength when an electron "jumps" from one energy level, characterized by the quantum number n, to another?

I need a STRONG explanation of why B is the answer please and not E

a. n = 2 to n = 1

b. n = 3 to n = 2

c. n = 3 to n = 1

d. n = 1 to n = 3

e. n = 4 to n = 1

Answer 1

The energy levels of the hydrogen atom is
  
And the transition energy from the level n to level m is
   
   
Let use give a label for the overall constant
   
And so,
   
   ..........(1)
In the tabular form
  

options	n	m	(eqn 1)	Comments
a	2	1	1.333 A
b	3	2	7.2 A	Maximum
c	3	1	1.125 A
d	1	3	- 1.125 A (absorption line )
e	4	1	1.067 A

So, the transition from n = 3 to n = 2 has the maximum wavelength. So, option b is correct.

answered by: anonymous