The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is J mol-1. Given: RH = 2.18 10-11 ergs.
- 9.835 1012
- 1.635 10-11
- 1.635 10-18
- 9.835 105
Answer
(4) 9.835 105
Solution
En = - RHn2
E = RH ( 112 - 122 )
= 2.18 10-11 34
= 1.635 10-11 erg per atom
= 1.635 10-18 J per atom
For 1 mol of atoms:
E = 1.635 10-18 6.022 1023
9.8 105 J mol-1
The value is 9.835 105 J mol-1 (closest option).
Answer: (4)