NEET-XII-Physics

43: Bohr's Model and Physics of the Atom

with Solutions -
  • #2
    The first excited energy of a He+ ion is the same as the ground state energy of hydrogen. Is it always true that one of the energies of any hydrogen-like ion will be the same as the ground state energy of a hydrogen atom?
    Ans : The energy of hydrogen ion is given by
    `` {E}_{\,\mathrm{\,n\,}}=-\frac{(13.6\,\mathrm{\,eV\,}){Z}^{2}}{{n}^{2}}``
    For the first excited state (n = 2), the energy of He+ ion (with Z = 2) will be `` -``13.6 eV. This is same as the ground state energy of a hydrogen atom.
    Similarly, for all the hydrogen like ions, the energy of the (n `` -`` 1)th excited state will be same as the ground state energy of a hydrogen atom if Z = n.
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