Electrons

The electron is a subatomic particle, symbol e⁻ or β⁻, with a negative elementary electric charge. Electrons belong to the first generation of the Lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron has a mass that is approximately 1/1836 that of the Proton.

Properties

Electrons have a rest mass of about 9.109 × 10⁻³¹ kilograms, or about 0.511 MeV/c². They have a negative charge of 1.602 × 10⁻¹⁹ coulombs, which is considered the basic unit of electric charge. The intrinsic angular momentum (spin) of an electron is a half-integer value in units of ħ, which means they are classified as Fermions. Electrons also exhibit properties of both particles and waves, a behavior explained by the theory of Quantum mechanics.

Role in atoms

Electrons are one of the three main types of particles that make up Atoms, along with protons and Neutrons. Electrons are located in the electron cloud outside the nucleus, and they balance the positive charge of the protons in the nucleus. Electrons determine the chemical properties of an atom and participate in chemical reactions.

Discovery

The existence of the electron was first theorized by Richard Laming in the mid-19th century, but it was not until 1897 that J.J. Thomson conclusively demonstrated its existence through his work on cathode rays. Thomson's experiments involved passing electric currents through gases at low pressure, and observing the resulting rays that were emitted. He showed that these rays were composed of negatively charged particles, which he called "corpuscles," later renamed electrons.

Applications

Electrons play an essential role in numerous physical phenomena, such as electricity, Magnetism, and thermal conductivity, and they are also used in various applications such as Electron microscopes, welding, and cathode ray tubes.

Quantum properties

In the field of quantum mechanics, the electron has several notable properties. It has an intrinsic spin of 1/2, which is a fundamental component of quantum theory. The electron also exhibits the phenomenon of wave-particle duality, which is explained by the Heisenberg Uncertainty Principle.

See also

• Proton
• Neutron
• Atom
• Quantum mechanics
• Lepton