• # question_answer A beam of 13.0 eV electrons is used to bombard gaseous hydrogen. The series obtained in emission spectra is/are A)  Lyman series             B)  BalmerC)  Brackett                     D)  All of these

As the electron beam is having energy 13 eV, it can excite the atom to the states whose energy is less than or equal to$0.6\,eV(13.6-13).$${{E}_{5}}=0.544\,eV\And \,{{E}_{4}}$$=0.85\,eV.$ So, the electron beam can excite the hydrogen gas maximum to 4th energy state, hence, the transit electron can come back to ground state from either of four states (1, 2, 3, and 4), thus, emitting Lyman, Balmer, Paschen, and Brackett series. Hence, the correction option is [d].