Same chapter3 marksDifficulty: Medium
Find the wavelength of the radiation emitted when an electron in a hydrogen atom falls from the third orbit to the second. Take the Rydberg constant as 1.097 × 107 m−1.
Atoms and Nuclei
3 marksDifficulty: Medium
State the postulates of Bohr's model of the atom.
Original Khojo Papers practice question — not from a past board paper.
Answer
The electron revolves round the nucleus only in certain permitted circular orbits, in which it does not radiate energy. The angular momentum of the electron in such an orbit is an integral multiple of h/2π. An electron radiates or absorbs energy only when it jumps from one permitted orbit to another, the frequency being given by hν = E2 − E1.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The model explained the hydrogen spectrum but not that of atoms with more than one electron.
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