According to Bohr's model, an electron transitioning from the n=4 to n=2 state in a hydrogen-like ion emits a photon with a wavelength of 486 nm. What is the atomic number (Z) of this ion?

The de-Broglie wavelength of an electron in the ground state of the hydrogen atom is

A singly ionized helium atom (He+) has an electron in its second excited state. According to the Bohr model, what is the ratio of its energy to the energy of an electron in the first excited state of a hydrogen atom?

The energy of an electron in the first and second excited states of a hydrogen atom are $T_1$ and $T_2$, respectively. According to Bohr's model, what is the ratio $T_1 : T_2$?

The ratio of the wavelengths of the first line of the Lyman series and the first line of the Balmer series of the hydrogen spectrum is:

A diatomic molecule is made of two masses ${m_1}$ and ${m_2}$ which are separated by a distance $r$. If we calculate its rotational energy by applying Bohr’s rule of angular momentum quantization, its energy will be given by ($n$ is an integer)

The Bohr model is not applicable to which of the following?

The total energy of an electron in an atom in an orbit is ${\rm{ - 3}}{\rm{.4eV}}$. Its kinetic and potential energies are, respectively:

For principal quantum number $n = 3$, the possible values of orbital quantum number $'l'$ are

The radius of the first Bohr orbit in a hydrogen atom is 0.53 Å. What is the radius of the third Bohr orbit?

The electron in a hydrogen atom makes a transition from $n = {n_1}$ to $n = {n_2}$ state. The time period of the electron in the initial state is eight times that in the final state. The possible values of ${n_1}$ and ${n_2}$ are