Write a chemical equation for hno3 (aq) showing how it is an acid or a base according to the arrhenius definition

An arrhenius acid increases the concentration of H3O + (or H + they're the same for the sake of acids and bases) in an aqueous solution.

HNO3 (aq) (known as nitric acid) is made up of two principle particles. A nitrate ion NO3-, and a hydrogen ion H+, which is what determines that it will be an acid, due to this hydrogen ion. The equation will be:

HNO3 (aq) + H2O (l) - - > H3O + (aq) + NO3 - (aq)

Because HNO3 (aq) increases H3O + concentration in the solution by donating its H + ion to the water, it acts as an arrhenius acid.