Electron Mass

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.

1.0Electron Mass Value

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 = $9.1091 0^{- 31} k g$

2.0Unit of Electron Mass

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).

Unit of Electron Mass	Value of mass
Mass of Electron in AMU	5.48579909070(16)×10^-4amu
Mass of Electrons in grams	9.10938356(11) × 10^-28 grams
Mass of Electron in eV	0.5109989461(31) MeV/c²
Mass of Electron in kg	9.10938356(11) × 10^-31 kg

3.0Dimensional Formula of Electron Mass

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.

4.0Electron Mass and Charge

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:

Electron Mass	Electron Charge
Electron mass is the measure of the amount of matter carried by an electron.	Electron charge is the electronic charge (negative) carried by an electron.
The SI unit of the electron is kilogram (kg).	SI unit of electron charge is coulombs (C)
The electron mass plays a crucial role in determining the size and energy levels of the atom.	The electron charge is a far more significant property which determines the chemical and physical properties of atoms.
The mass of an electron is more prominent in determining how it interacts with the gravitational field affecting motion.	The electron charge determines how the electron interacts in electromagnetic fields, meaning electric and magnetic fields.
Value: 9.10938356(11) × 10^-31 kg	Value: –1.602 × 10^–19 C

5.0Significance of Electron Mass in Physics

The Mass of the electron is of great importance in several fields of physics, some of them include:

Atomic Structure: The electron mass influences the size of atomic orbitals. A more mobile electron results in a larger orbital radius, which in turn changes atomic properties like ionisation energy and chemical reactivity.
Quantum Mechanics: In quantum mechanics, the electron mass (Me) is a relevant parameter of the Schrödinger equation (SE). It governs the electron's motion in atoms, influencing energy levels and the wave function.
Relativity: Although electron mass is much reduced, it still relates to relativistic effects. Due to the relativistic effects described by Einstein's theory (E = mc²), the effective mass of electrons increases if they move at high velocities.

6.0Practical Applications of Electron Mass

The electron mass is essential in various practical applications, which include:

Semiconductors and Electronics: The electron mass determines the speeds at which electrons can travel in the material. This is crucial for performing electronic devices such as transistors used in computers and smartphones.
Quantum Computing: The mass of the electron has an important function in quantum computation, in which electrons are built to make the qubits perform even more efficient and powerful computing.
Medical Imaging: The electron mass is employed in electron microscopes, which, when under-sampled, yield images of resolution (as compared with traditional light microscopes). It finds uses in biology and materials science.
Space Exploration: Knowing the electron mass is important for studying cosmic rays and particle behaviour in space. This is also crucial for satellite and spacecraft technologies.