The electrons are the negatively charged subatomic particles which revolve around the nucleus of the building block of every material, “the atom”. These electrons are smaller than the atoms in size. So, the common question is: do these particles possess any mass? The answer to this question is yes; electrons do have mass, which is known as the Electron mass. Although extremely small, this mass plays a crucial role in determining every behaviour of atoms, from chemical reactions to the formation of matter itself.
The electron mass value refers to the actual mass of an electron, a constant value that plays an important role in understanding how electrons behave in different conditions and fields. This mass is extremely small compared to the masses of the other subatomic particles. For example, the mass-proton's Mass is approximately 1836 times heavier than the electron's.
Electron mass value =
The unit of electron mass used in the International System of Units (SI) is the kilogram (kg), but in particle physics, electron mass is usually calculated in other terms, such as atomic mass units (AMU) or electron volts (eV).
A dimensional formula is the expression of a certain quantity in terms of the fundamental physical dimensions, which are mass, length, time, etc. The dimensional formula of electron mass can be written as:
[M1 L0T0]
The 0 here shows that the mass of an electron is a unit of mass in the SI system and is not dependent on length and time.
The electron mass and charge are the two fundamental properties of an electron revolving around the nucleus of an atom. Both properties are very important aspects of electrons with slight differences:
The Mass of the electron is of great importance in several fields of physics, some of them include:
The electron mass is essential in various practical applications, which include:
(Session 2025 - 26)