Question

Maximum number of spectral lines obtained when
electrons in H-atom sample de-excite from fourth
excited state to ground state is
(1) 15
(3) 8
(2) 10
(4) 6
​

Answer 1

10

ex:

(n exc - n ground)×(n exc- n ground -1)/2

fourth excited state is n=5

(5-0)×(5-0-1)/2

=10

Answer 2

Answer:

Ur ans is 10

If an electron moves from n=6 to 5 we get a spectral line. Then from n=5 to 4 we get one and so on giving us a maximum of 5 spectral lines.

Its a similar type of ans....it ll help u to find ur ans