## Question

The ionization energy of hydrogen in excited state is +0.85 eV. What will be the energy of the photon emitted when it returns to the ground state?

### Solution

12.75 eV

Energy of H-atom in the ground state

= –13.6 eV.

Ionization energy of the hydrogen in excited state equal to +0.85 eV means

Energy of H-atom in the excited state = –0.85 eV

∴ Energy emitted = –0.85 – (–13.6 eV)

= 12.75 eV.

#### SIMILAR QUESTIONS

Calculate the energy of a mole of photons of radiations whose frequency is ?

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