question_answer

The first excitation potential of hydrogen atom in the ground state is :

A)  13.6 V                                  

B)  3.4 V

C)  10.2 V                                  

D)  1.89 V

Correct Answer: C

Solution :

                From Bohrs concept, energy of atom is nth level is \[E=\frac{Rhc}{{{n}^{2}}}\] Energy required to raise an electron from ground state\[(n=1)\]to first excited state\[(n=2)\]is \[E={{E}_{2}}-{{E}_{1}}\]                               \[E=-3.4-(13.4)\]                 \[E=-3.4+13.4=10.2\,eV\]