Electron

Definition

An electron is a subatomic particle with a negative electric charge. It orbits the nucleus of an atom in various energy levels or shells.

5 Must Know Facts For Your Next Test

1. Electrons are much smaller in mass compared to protons and neutrons.
2. The arrangement of electrons around an atom determines its chemical properties and reactivity.
3. Electrons can gain or lose energy by moving between different energy levels or orbitals.
4. In chemical reactions, atoms often gain, lose, or share electrons to achieve a full outer shell of electrons.
5. Electron pairs form covalent bonds between atoms in molecules.

Review Questions

• What is the charge of an electron?
• How do electrons affect the chemical properties of an atom?
• What happens when an electron moves between energy levels?

Related terms

Proton: one sentence definition

Neutron: one sentence definition

Valence Electrons: one sentence definition