The $Bohr$ model of an atom could not account for:

If the series limit of wavelength of the Lyman series for the hydrogen atom is $912 \ \mathring{A}$,then the series limit of wavelength for the Balmer series of radiation which may be emitted is :

The energy (in $eV$) associated with the electron in the $1^{st}$ orbit of $Li^{2+}$ is

The ratio of the energy of a photon of $2000 \ \mathring{A}$ wavelength radiation to that of $4000 \ \mathring{A}$ radiation is

If the ratio of energies of an electron in the excited states of $H$ and $Li^{2+}$ is $1: 9$,the radius ratio of the electron in the same excited states of $H$ and $Li^{2+}$ is

What is the energy associated with the first orbit of $He^{+}$?