MCQ
The wavelength of light emitted from second orbit to first orbits in a hydrogen atom is
- ✓$1.215 \times {10^{ - 7}}m$
- B$1.215 \times {10^{ - 5}}m$
- C$1.215 \times {10^{ - 4}}m$
- D$1.215 \times {10^{ - 3}}m$
✓
Answer
Correct option: A.
$1.215 \times {10^{ - 7}}m$
a
(a) Energy radiated $E = 10.2\,eV = 10.2 \times 1.6 \times {10^{ - 19}}J$
(a) Energy radiated $E = 10.2\,eV = 10.2 \times 1.6 \times {10^{ - 19}}J$
==> $E = \frac{{hc}}{\lambda }$ ==> $\lambda = 1.215 \times {10^{ - 7}}m$
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