Atoms & Nuclei

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112 of 239

Question 112 of 239

An electron of hydrogen atom on an excited state is having energy En=−0.85eV{E}_{n}=-0.85eV. The maximum number of allowed transitions to lower energy level is _______.

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Answer: 6

Energy of nth{n}^{th} orbit is given by, En=−13.6n2{E}_{n}=-\dfrac{13.6}{{n}^{2}}
⇒−13.6n2=−0.85⇒n=4\Rightarrow -\dfrac{13.6}{{n}^{2}}=-0.85 \Rightarrow n=4
No of transition,
=n(n−1)2=4(4−1)2=6=\dfrac{n(n-1)}{2}=\dfrac{4(4-1)}{2}=6

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