How do acidifiers affect the pH of a solution?

Acidifiers are substances that, when added to a solution, lower the pH by increasing the concentration of hydrogen ions (H+). This results in a more acidic environment. The correct answer highlights that acidifiers effectively reduce the pH of a solution, but they do not act as buffers, which means they don’t resist changes to pH upon the addition of acids or bases. Rather, they create a substantial shift towards acidity.

When considering the other options, the choice stating that acidifiers maintain a stable pH without changing it is incorrect because acidifiers inherently alter the pH when added. Similarly, the idea that they elevate the pH significantly contradicts their fundamental role as acidifiers, while the notion that they only affect alkaline substances ignores their ability to lower pH in any aqueous solution, regardless of its initial pH level.