A
buffering agent is a weak acid or base used to maintain the acidity (
pH) of a
solution near a chosen value after the addition of another acid or base. That is, the function of a buffering agent is to prevent a rapid change in pH when acids or bases are added to the solution. Buffering agents have variable properties—some are more soluble than others; some are
acidic while others are
basic. As pH managers, they are important in many
chemical applications, including
agriculture,
food processing,
biochemistry,
medicine and
photography.