The energy required to ionise a hydrogen like ion in its ground state is 9 Rydbergs. What is the wavelength of the radiation emitted when the electron in this ion jumps from the second excited state to the ground state ?
Solution
So, ionisation energy = (13.6 Z<sup>2</sup>) eV
<br><br>= 9 $\times$ 13.6 eV
<br><br>$${1 \over \lambda } = R{Z^2}\left( {{1 \over {{1^2}}} - {1 \over {{3^2}}}} \right)$$
<br><br>= 1.09 $\times$ 10<sup>7</sup> $\times$ 9 $\times$ ${8 \over 9}$
<br><br> = 11.4 nm
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Bohr's Model of Hydrogen Atom
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