Question

Assertion (A): The potential energy of an electron revolving in any stationary orbit in a hydrogen atom is positive.

Reason (R): The total energy of a charged particle is always positive.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

• Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).

• Assertion (A) is true, but Reason (R) is false.

• Assertion (A) is false and Reason (R) is also false.

Answer 1

Assertion (A) is false and Reason (R) is also false.

Explanation:

The potential energy (u) of an electron ina hydrogen atom is given by: 

u = `-(ke^2)/r`

As u is negative, Assertion (A) is false as it incorrectly states that the potential energy is positive.

The total energy (E) of an electron in a hydrogen atom is given by:

E = `-(ke^2)/(2r)`

The negative total energy indicates that the electron is bonded to the nucleus. The Reason (R) mistakenly assumes that the total energy of a charged particle is always positive. In bound systems, such as the hydrogen atom, the overall energy is negative.