Question
Question: What electronic transition in Li<sup>2+</sup> produces the radiation of same wavelength as the first...
What electronic transition in Li2+ produces the radiation of same wavelength as the first line in the Balmer’s series of Hydrogen spectrum-
A
n2 = 3 to n1 = 2
B
n2 = 6 to n1 = 3
C
n2 = 9 to n1 = 6
D
n2 = 9 to n1 = 8
Answer
n2 = 9 to n1 = 6
Explanation
Solution
First line in balmer series means transition from n = 3 to n = 2. Now, 9th orbit of Li2+ has same energy as third orbit of 'H' atom & 6th orbit of Li2+ has same energy as second orbit of 'H' atom. So n = 9 to n = 6 transition in Li2+ would have same wavelength as first line in balmer series of H–spectrum.