Chapter 30, Problem 100A

To determine

To calculate:

The kinetic energy with which the electron can be ejected from an atom.

Answer to Problem 100A

The kinetic energy with which the electron can be ejected from an atom is $0.4\text{MeV}$ .

Explanation of Solution

Given:

For An hydrogen atom,

Energy of photon $=14.0\text{eV}$

Formula Used:

Formula to calculate the kinetic energy of electron,

  $K{E}_e=hf-BE$

Where,

  $hf$ : Photon Energy

  $BE$ : Binding energy or ionization energy

Kinetic Energy of electron=Energy of photon $-$ Energy of ionization.

Calculation:

Formula to calculate the kinetic energy of electron,

  $K{E}_e=hf-BE$

Substitute all the values in given formula,

As the ionization energy of hydrogen is $13.6\text{MeV}$ .The kinetic energy will be given as,

  $\begin{array}{l}K{E}_e=14-13.6\\ =0.4\text{MeV}\end{array}$

Conclusion:

The kinetic energy with which the electron can be ejected from an atom is $0.4\text{MeV}$ .