Nuclear Physics And Radioactivity Question 89

Question: The electron in a hydrogen atom makes a transition from an excited state to the ground state. Which of the following statements is true?

Options:

A) Its kinetic energy increases and its potential and total energies decrease

B) Its kinetic energy decreases, potential energy increases and its total energy remains the same

C) Its kinetic and total energies decrease and it potential energy increases

D) Its kinetic, potential and total energies decrease

Show Answer

Answer:

Correct Answer: A

Solution:

[a] For hydrogen and hydrogen-like atoms $ E_{n}=-13.6\frac{z^{2}}{n^{2}}eV $ $ U_{n}=2E_{n}=-27.2\frac{z^{2}}{n^{2}}eV $ and $ K_{n}=| E_{n} |=13.6\frac{z^{2}}{n^{2}}eV $ From these three relations we can see that as n decreases, $ K_{n} $ will increase but $ E_{n} $ and $ U_{n} $ will decrease.