Question

Ionisation energy of hydrogen atom is 13.6 eV. Then the energy required to ionise a hydrogen atom in which the electron is in the second orbit from the nucleus is (eV)

• A. -13.6
• B. 3.4
• C. 10.2
• D. 13.6

Answer 1

Answer: (B)

3.4

Answer 2

E = $\frac{13.6}{n^2} = \frac{13.6}{Z^2} = \frac{13.6}{4}$ = 3.4 eV