Which of the following particles has almost no mass? proton neutron electron

Electron has almost no mass.

Explanation:

Mass is defined as the actual matter that is contained in a substance. At an atomic level, it is expressed in atomic mass units.

The given options are the 3 subatomic particles.

Mass of the given subatomic particles are:

Proton = 1.007276u

Neutron = 1.008664u

Electron = 0.0005485u

Mass of neutron is slightly more than the mass of proton.

From the above information, it is visible that electron has a negligible mass.

Hence, the correct answer is electron.