1. Plural of hydronium; positively charged ions (H₃O⁺) formed when a hydrogen ion bonds with a water molecule, commonly found in acidic solutions.
Usage: chemistry; technical term

Examples

• In acidic solutions, hydroniums are responsible for the characteristic properties of acids.
• The concentration of hydroniums determines the pH of a solution.
• When hydrogen chloride dissolves in water, it produces hydroniums and chloride ions.
• Hydroniums migrate toward the cathode during electrolysis of acidic water.
• The formation of hydroniums explains why acids conduct electricity in aqueous solutions.