An electron is a subatomic particle with a negative electrical charge that orbits the nucleus of an atom. Electrons are one of the fundamental particles that make up the structure of atoms, along with protons and neutrons. Here are some key points about electrons: Properties of Electrons: Charge: Electrons have a negative electrical charge, denoted by − � −e, where � e is the elementary charge. The charge of an electron is approximately − 1.602 × 1 0 − 19 −1.602×10 −19 coulombs. Mass: Electrons have a very small mass compared to protons and neutrons. The mass of an electron is approximately 9.109 × 1 0 − 31 9.109×10 −31 kilograms. Size: Electrons are point-like particles with no known internal structure. They are considered to be elementary particles, meaning they are not made up of smaller constituents. Wave-Particle Duality: Electrons exhibit both particle-like and wave-like behavior, according to the principles of quantum mechanics. This duality is described by the wave function, which gives the probability of finding an electron at a particular location.