Enter a chemical equation for HI (aq) showing how it is an acid or a base according to the Arrhenius definition. Consider that strong acids and bases dissociate completely. Express your answer as a chemical equation. Identify all of the phases in your answer.

HI (aq) → H⁺ (aq) + I⁻ (aq)

HI (aq) + H₂O (l) → H₃O⁺ (aq) + I⁻ (aq)

Explanation:

The Arrhenius acid concept indicates that a substance behaves like acid if it produces hydrogen ions H⁺ or hydronium ions H₃O⁺ in water. A substance will be classified as a base if it produces OH⁻ hydroxide ions in water. This way of defining acids and bases works well for aqueous solutions.

When we mix HI (aq) and water, we are increasing [H₃O⁺]

HI (aq) → H⁺ (aq) + I⁻ (aq)

HI (aq) + H₂O (l) → H₃O⁺ (aq) + I⁻ (aq)