Adding ammonia (NH3) to water makes NH4. This will cause the pH of the solution to:.

pH increases

Explanation:

The ammonia, NH₃, reacts with water, H₂O, as follows:

NH₃ + H₂O → NH₄⁺ + OH⁻

That means when NH₃ is added to water, some OH⁻ is produced. As [H⁺] is inversely proportional to [OH⁻], the increase of OH⁻ causes the decrease og H⁺. And when H⁺ decreases,

pH increases

particle   p is an electron and particle q is a neutron