Neutralization: definition in chemistry
Neutralization: A reaction between an acid and a base that produces a salt and, usually, water, canceling out their acidic and basic properties.
In water, the key step is hydrogen ions from the acid combining with hydroxide ions from the base: H⁺ + OH⁻ → H₂O. Neutralization is exothermic, so the mixture warms up. The final solution is exactly neutral only when a strong acid reacts with an equal amount of a strong base; with a weak acid or a weak base it may end up slightly basic or acidic.
Examples
- HCl + NaOH → NaCl + H₂O
- Antacid tablets neutralizing excess stomach acid
- Farmers spreading lime to neutralize acidic soil
- Baking soda used to neutralize spilled acid in a lab
On the periodic table
Common neutralizing agents are compounds of group 1 and group 2 metals, such as sodium hydroxide, magnesium hydroxide and calcium carbonate.