Electron

Definition

An electron is a subatomic particle with a negative electric charge and negligible mass compared to protons and neutrons. Electrons play a key role in electricity, magnetism, and thermal conductivity.

5 Must Know Facts For Your Next Test

1. Electrons have a charge of approximately $-1.602 \\times 10^{-19}$ coulombs.
2. The mass of an electron is about $9.109 \\times 10^{-31}$ kilograms.
3. In atoms, electrons are found in orbitals around the nucleus, determining chemical properties.
4. Electrons are responsible for the flow of electric current in conductive materials.
5. When an atom gains or loses an electron, it becomes an ion with a net positive or negative charge.

Review Questions

• What is the approximate charge of an electron?
• How does the mass of an electron compare to that of a proton?
• What happens to an atom when it loses or gains electrons?

Related terms

Proton: A subatomic particle found in the nucleus with a positive electric charge equal in magnitude to that of an electron.

Neutron: A subatomic particle found in the nucleus with no electric charge and a mass slightly greater than that of a proton.

Ion: An atom or molecule that has gained or lost one or more electrons, resulting in a net electric charge.