Question

The excitation energy of first excited state of hydrogen like atom is40.8 eV .Find energy needed to remove the electron to form the ion

Answer 1

40.8 eV needed to remove from first excited to level and to remove from ground level add 13.6 eV to it I. e. 54.4 eV

Answer 2

Answer:

54.4 eV of energy needed to remove the electron to form the ion.

Explanation:

$E_n=-13.6\times \frac{Z^2}{n^2}ev$

where,

$E_n$ = energy of $n^{th}$ orbit

n = number of orbit

Z = atomic number

First excited state = 1 → 2

$40.8eV=E_{2}-E_1$

$40.8eV=(-13.6\times \frac{Z^2}{2^2}eV)-(-13.6\times \frac{Z^2}{1^2}eV)$

Z = 2 amu

Energy required to remove an electron to form the ion.

1 → ∞

$E=(-13.6\times \frac{2^2}{\infty ^2}eV)-(-13.6\times \frac{2^2}{1^2}eV)$

$=54.4 eV$

54.4 eV of energy needed to remove the electron to form the ion.