The wavelength of spectral line obtained in the spectrum of Li2+ ion, when the transition takes place between two levels whose sum is 4 and difference is 2, is
- 1.14 10-6 cm
- 2.28 10-6 cm
- 1.14 10-7 cm
- 2.28 10-7 cm
Answer
(1) 1.14 10-6 cm
Solution
n2 + n1 = 4 and n2 - n1 = 2 n2 = 3, n1 = 1
For Li2+, Z = 3:
1 = RH Z2 ( 1n12 - 1n22 )
= 109677 9 (1 - 19 )
= 109677 8 = 877416 cm-1
= 1877416 cm = 1.14 10-6 cm
Answer: (1)