Chemicals called are those that can combine with h+ when hydrogen ions are in excess, and release h+ when hydrogen ion levels are low. the function of these chemicals is to minimize changes in ph.

Explanation:

When an acid or base is added to a solution then any resistance by the solution in changing the pH of the solution is known as a buffer.

This is because a buffer has the ability to not get affected by the addition of small amounts of an acid or a base. As a result, it helps in maintaining the pH of the solution.

Thus, we can conclude that chemicals called buffer are those that can combine with when hydrogen ions are in excess, and release when hydrogen ion levels are low. The function of these chemicals is to minimize changes in pH.