_____________n = 4 ____________ n = 3 ____________ n = 2 ____________ n = 1 Since, at n = 1, the population of electrons is maximum at ground state. So, maximum excitation will take place from n = 1 to n = 2. Hence n = 2 is the possible excited state ∴ Energy of 'H' atom, E=−13.6×