How does an acidifier differ from a buffer?

An acidifier is a substance that specifically lowers the pH of a solution, making it more acidic. This function of an acidifier is critical when there is a need to adjust pH levels for optimal nutrient availability or to enhance the effectiveness of certain herbicides or pesticides, which may perform better in acidic conditions. However, an acidifier does not have the ability to maintain that lowered pH over time; it simply acts to decrease the pH at the moment of addition.

On the contrary, a buffer is designed to resist changes in pH when small amounts of acid or base are introduced into a solution. Buffers work by providing a mechanism that either neutralizes added acids or bases, thereby stabilizing the pH of a solution over time. Therefore, while acidifiers lower pH momentarily, they do not have the capacity to maintain that pH, distinguishing them from buffers.

The other options do not accurately capture the specific role of an acidifier in relation to how it differs from a buffer.