10. An electron in a hydrogen atom ...
Question

# 10. An electron in a hydrogen atom in its ground state absorbs twice its ionisation energy what is the wavelength of the emitted electron? (A) 3.32 x 10-70m (B) 33.2 x 10-10 m (C) 0.33 x 104m (D) 0.33 x 106m

JEE/Engineering Exams
Chemistry
Solution
452
5.0 (2 ratings)
exerteom Ale. to question ( -(I E) ) Encrgy supplied ( =2 times 1 € ) ( therefore K E=2 times I E-I E=I E ) But me know ( I in=13 cdot 6 times frac{z^{2}}{n^{2}} e^{V} ) [ begin{array}{l}I E=13 cdot 6 text { and } n=1 text { So } k E=13 cdot 6 text { e } Vend{array} ] Now Are to debeoglie, wavelength = ( frac{text { plank comstant }}{sqrt{2 m k E}} ) ( begin{aligned} k E &=13.6 times 1.6 times 10^{-19} mathrm{J} m &=9.1 times 10^{-31} mathrm{kg} h &=6.62 times 10^{-34} mathrm{Js} text { So. } & text { wavelength }=frac{6 cdot 62 times 10^{-34}}{sqrt{2 times 9.1 times 10^{-31} times 13.6 times 1.6}} &=frac{6.62 times 10^{-34+25}}{19.9} mathrm{x} 10^{-19} &=3.32 times 10^{-10} mathrm{m} &=3.32 mathrm{A} end{aligned} )