Write a chemical equation for nh4+(aq) showing how it is an acid or a base according to the arrhenius definition. express your answer as a chemical equation. identify all of the phases in your answer.

NH4+(aq)  → NH3(aq) + H+(aq)

Explanation:

Following arrhenius, an acid can be defined as:

An Arrhenius acid is a substance that, when added to water, increases the concentration of H+ ions in water.

NH4+(aq)  → NH3(aq) + H+(aq)

The ammonium ion acts as a weak acid in aqueous solution, dissociating into ammonia and a hydrogen ion.

An Arrhenius base is a substance that, when added to water, increases the concentration of OH- ions in water.

NH4+(aq) will not dissciate in OH- ions. So it's not a base, but an acid.