Is it true that when adding an acid to an alkali makes pH number go up?

A neutralization process take place.It emmits energy as heat,so temperature increase.

Answer:

Neutralization is often exothermic (produces heat) A typical example is is the mixing of sodium hydroxide and hydrochloric acid. However endothermic neutralization reactions (the reaction cools the solution) do happen. A simple example is the mixing of baking soda and acetic acid.