When an electron jumps from a lower to a higher orbit,its energy

Maximum number of spectral lines possible when an electron jumps from $5^{th}$ excited state to ground state in a sample containing only one Hydrogen atom will be

For $Li^{2+}$ ion,the ratio of radii $r_2 : r_5$ will be

For any given series of spectral lines of atomic hydrogen,let $\Delta \bar{\nu} = \Delta \bar{\nu}_{\max} - \Delta \bar{\nu}_{\min}$ be the difference in maximum and minimum wavenumbers in $cm^{-1}$. The ratio $\Delta \bar{\nu}_{\text{Lyman}} / \Delta \bar{\nu}_{\text{Balmer}}$ is

$A$ certain transition in the hydrogen spectrum from an excited state in one or more steps gives rise to a total of $10$ lines. The number of lines lying in the visible spectrum is:

The wave number of the first line of the Balmer series of $H$ atom is $15200 \ cm^{-1}$. What is the wave number of the first line of the Lyman series of $Li^{2+}$? (in $cm^{-1}$)