electrons – negatively charged particles in atoms
what is an electron?
An electron is a subatomic particle with a negative electric charge. Electrons are found in orbitals or energy levels surrounding the nucleus of an atom.
basic properties
- symbol: e⁻
- charge: -1
- mass: ~1/1836 of a proton
- location: outside the nucleus, in electron shells
discovery
j.j. thomson discovered the electron in 1897 using cathode ray tube experiments. This was the first subatomic particle ever identified.
role of electrons
- Balance the charge of protons in atoms
- Involved in all chemical reactions and bonding
- Define the ion state of an atom (e.g., losing or gaining electrons)
- Determine the electron configuration and properties of elements
electrons and chemical bonding
Electrons in the outer shell (valence electrons) are key to:
electron cloud model
Instead of fixed orbits, modern quantum theory describes electrons as existing in a cloud of probabilities around the nucleus.
see also
disclaimer
This article is intended for educational and academic use only and supports learning in chemistry and physics within a MediaWiki-based environment.