question_answer

If the binding energy of the electron in a hydrogen atom is \[13.6\] eV, the energy required to remove the electron from the first excited state of \[L{{i}^{2+}}\] is                     [AIEEE 2003]

A) \[30.6\] eV

B) \[13.6\] eV

C) \[3.4\] eV

D) \[122.4\] eV

Correct Answer: A

Solution :

[a] Orbital energy,

For first excited state,

= - 30.6 eV

lonisation energy for first excited state of  is 30.6 eV.