question_answer 118)

  The Balmer series in the hydrogen spectrum correspond to the transition from \[{{n}_{1}}=2\]to \[{{n}_{2}}=3,4.....\]This series lie in the visible region. Calculate the wave number of line associated with the transition in Balmer series when the electron moves to \[n=4\] orbit.\[({{R}_{H}}=109677c{{m}^{-1}})\]

Answer:

  We know \[\overset{-}{\mathop{v}}\,=R{{z}^{2}}\left[ \frac{1}{n_{1}^{2}}-\frac{1}{n_{2}^{2}} \right]\] \[=109677\times {{1}^{2}}\left[ \frac{1}{{{2}^{2}}}-\frac{1}{{{4}^{2}}} \right]\]\[=109677\times \left[ \frac{3}{16} \right]=20564.4c{{m}^{-1}}\]