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How does the Arrhenius theory describe acids and bases in water?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

The Arrhenius theory, introduced by Svante Arrhenius in 1887, defines acids and bases based on their behavior in aqueous solutions.12

Acids: Substances that dissociate in water to increase the concentration of hydrogen ions ( $H^{+}$ ), which are more accurately described as hydronium ions ( $H_{3} O^{+}$ ) because hydrogen ions do not exist independently in water.13
Bases: Substances that ionize in water to increase the concentration of hydroxide ions ( $O H^{-}$ ).13

This theory explains acid-base reactions as the combination of hydrogen and hydroxide ions to form water, resulting in the production of a salt. A significant advantage of this framework is its quantitative nature; by measuring the concentration of these ions—often through electrical conductivity—chemists can determine the relative strength of acids and bases using dissociation constants. While later theories expanded upon these definitions to include nonaqueous solvents, the Arrhenius theory remains a fundamental quantitative description of chemical behavior in water.132