Question

The ionisation potential of hydrogen atom is $13.6eV$. The energy required to remove an electron from the second orbit of hydrogen will be

• A. $27eV$
• B. $13.6eV$
• C. $3.4eV$
• D. None of these

Answer 1

Answer: (C)

$3.4eV$

Ionisation energy of hydrogen atom is equal to the magnitude of energy of its first orbit i.e. $E_1=13.6eV$

Magnitude of energy of 2nd orbit, $E_2=\frac{13.6}{2^2}=3.4eV$

Thus energy required to remove an electron from second orbit is equal to $3.4eV$.