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How does gaining or losing electrons turn an atom into an ion?
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subatomic particle
The Large Hadron Collider (LHC), the world's most powerful particle accelerator. At the LHC, located underground in Switzerland, physicists study subatomic particles.
An ordinary, neutral atom contains an equal number of positively charged protons and negatively charged electrons, which balances the atom's overall electrical charge. An ion is formed when this balance is disrupted through the loss or gain of electrons.12
- Positive Ions (Cations): When a neutral atom loses one or more electrons, it retains its original number of protons but now has fewer negative charges than positive charges. This results in a net positive charge, creating a cation.21
- Negative Ions (Anions): When a neutral atom gains one or more electrons, it possesses more negative charges than positive charges. This results in a net negative charge, creating an anion.21
Atoms often undergo these changes to achieve a more stable electron configuration, typically by filling or emptying their outermost valence shell. This process is fundamental to the formation of ionic bonds, where the resulting electrostatic attraction between oppositely charged ions holds them together in compounds.123