How much energy is required to ionise a H atom if the electron occupies `n = 5` orbit?

Explanation

` E_1 =- 13. 6 eV,`
` E_5 = ( - 13. 6)/(5^2) =- 0. 544 eV`
` =- 0.544 xx 1.6022 xx 10^(-19) J =- 8. 71 xx 10^(-20) J`
Thus , ` 0.544 eV` energy is required to ionise H-atom of electron is in ` 5^(th)` orbit .
Also , ` E_5 /E_1 = (0.544 )/( 13.6) = 0.04`.