Question

Number of possible spectral lines which may be emitted in Brackett series in $H$ atom, if electrons present in 9th excited level returns to ground level, are:

• A. 21
• B. 6
• C. 45
• D. 5

Answer 1

The correct option is D 5

The number of possible spectral lines that may be emitted in the Brackett series in H atom, if electrons present in 9th excited level returns to ground level, is 5.

The transitions are $9\to 4,8\to 4,7\to 4,6\to 4$ and $5\to 4$ respectively.