Find the number of spectral lines obtained when electron de-excites from 5th to the 1st energy level but no line is seen in balmer series ?

Asked by arunavamitra50 | 18th Jun, 2018, 06:35: PM

Expert Answer:

If the electron jumps from n2 = 5 to n1 = 1 then following are the transitions possible.

  1. 5→ 4
  2. 5→ 3
  3. 5→ 2
  4. 5 → 1
  5. 4 → 3
  6. 4→ 2
  7. 4→ 1
  8. 3 → 2
  9. 3→ 1
  10. 2 → 1

Hence there are 10 transitions and hence 10 spectral lines possible.

The general formula for the number of spectral lines emitted is

N space equals fraction numerator space left parenthesis n subscript 2 space end subscript – space n subscript 1 right parenthesis space left parenthesis n subscript 2 space – space n subscript 1 space plus space 1 right parenthesis over denominator 2 end fraction space space

space S o comma

space N space equals space fraction numerator left parenthesis space 5 space minus space 1 right parenthesis space left parenthesis space 5 space minus space 1 space plus space 1 space right parenthesis over denominator 2 end fraction space equals fraction numerator space 4 space X space 5 over denominator 2 end fraction space equals space 10 space

Answered by Ramandeep | 21st Jun, 2018, 02:40: PM