The shortest wavelength in Lyman series is 912 Å. The shortest wavalength in Paschen series is

Options

A. 8208 Å
B. 8082 Å
C. 8820 Å
D. 2088 Å

Answer

A

Explanation

For shortest wavelength of Lyman series,
`p=1` and `n=oo`
`:. 1/lambda_(1)=R(1/p^(2)-1/n^(2))=R(1/1-1/oo)`
`:. lambda_(1)=1/R` ...(1)
For shortest wavelength of Pashen series,
`p=3` and `n=oo`
`:. 1/lambda_(2)=R (1/p^(2)-1/n^(2))=R(1/9-1/oo)`
`:. lambda_(2)=9/R` ...(2)
From eq. (1) and (2) we have,
`lambda_(2)=9lambda_(1)=9xx912=8208 Å`