Bohr's Model for the Hydrogen Atom

According to the Bohr Theory, among the following, which transition in the hydrogen atom will give rise to the least energetic photon?

If n = 6, the correct sequence for filling of electrons will be :

The energy of the second Bohr orbit of the hydrogen atom is $-328 \mathrm{kJ} {\mathrm{mol}}^{-1}$. Hence, the energy of the fourth Bohr orbit would be

The number of orbitals possible for the following quantum numbers is/are

$\mathrm{n}=3,\hspace{0.17em}\hspace{0.17em}\mathrm{l}=2, \mathrm{m}=+2$

The radius of hydrogen atom in the ground state is  $0.53 \mathrm{\AA }.$  What is the radius of  ${\mathrm{Li}}^{2+}$  ion (Atomic number $=3$) in a similar state?

The radius of hydrogen atom in the ground state is  $0.53\mathrm{\AA }.$  The radius of  ${\mathrm{Li}}^{2+}$ ion (Atomic number = $3$) in first orbit is

For ${\mathrm{He}}^{+}$, a transition takes place from the orbit of radius $105.8\mathrm{pm}$ to the orbit of radius $26.45\mathrm{pm}$. The wavelength (in $\mathrm{nm}$ ) of the emitted photon during the transition is

Bohr radius, $\mathrm{a}=52.9 \mathrm{pm}$
Rydberg constant, ${\mathrm{R}}_{\mathrm{H}}=2.2\times {10}^{-18} \mathrm{J}$
Planck's constant, $\mathrm{h}=6.6\times {10}^{-34}\mathrm{Js}$
Speed of light, $\mathrm{c}=3\times {10}^8 {\mathrm{ms}}^{-1}$ ]

Using the Bohr's model calculate the speed of the electron and the orbital period in a hydrogen atom in the n=2 level.

For an electron placed in the third orbit of the hydrogen atom, calculate the number of revolutions per second made by it around the nucleus.

The ratio of the radius of any two orbits of hydrogen atom can be expressed as the ratio of 

According to Bohr theory, the electronic energy of a hydrogen atom in the ${\mathrm{n}}^{\mathrm{th}}$ Bohr atom is given by ${\mathrm{E}}_{\mathrm{n}}=\frac{21.76\times {10}^{-19}}{{\mathrm{n}}^2}\mathrm{J}$. Calculate the longest wavelength of light that will be needed to remove and electron from the third Bohr orbit of the ${\mathrm{He}}^{+}$ ion (If the wavelength is $x\times {10}^{-7}$(in meter) and $x$ is an integer. Report '$x$')

Sommerfeld modified Bohr's atomic model by adding elliptical orbitals.

Explanation of the fine structure of the hydrogen atom is the Sommerfeld's contribution to chemistry.

Sommerfeld modified Bohr's atomic model by adding _____ orbitals.

Sommerfeld offered a theoretical explanation of the fine structure of the _____.

Elliptical atomic orbital model is given by Bohr.