Question

Which particle in the atom has the smallest mass? electron proton neutron photon

Answer 1

The photon does not have mass. The neutron has almost the same mass as proton and their mass is a lot greater than electrons. So the particle with smallest mass should be electron.

Answer 2

Answer: Option (d) is the correct answer.

Step-by-step explanation:

An atom consists of three subatomic particles which are protons, electrons and neutrons.

Whereas a smallest quantum of electromagnetic radiation is known as photon. These remain always in motion and they travel at constant speed in a vacuum.

Mass of an electron is
`9.1 * 10^(-31)` kg

Mass of a proton is
`1.67 * 10^(-27)` kg

Mass of a neutron is
`1.67 * 10^(-27)` kg

On the other hand, a photon is mass less.

Hence, we can conclude that out of the given options photon is the particle which has the smallest mass.