How is pH paper is used to detect acids and bases?
The indicators used to identify acids and bases are large organic molecules that change color in acid or base. The most common acid/base indicator is litmus paper which changes color in the presence of an acid or base. Other indicators are specific and will change color only at a particular pH (H+ ion concentration).
Once you have determined if a substance is an acid or a base, you need to determine how strong (or concentrated) it is. The simplest measure of the strength of an acid or base is the concentration of H+ ion in the solution. The fastest way to determine pH is to use pH paper. It uses a broad range indicator to turns a series of colors from pH 1 to 14. The color change is then compared with a color chart to determine the pH. A high pH indicates a base, and a low pH indicates an acid. A pH near 7 indicates a neutral substance. Students should be aware that shampoos and soaps and most skin products are pH balanced near 7, to protect skin, hair and eyes.
The indicators used to identify acids and bases are large organic molecules that change color in acid or base. The most common acid/base indicator is litmus paper which changes color in the presence of an acid or base. Other indicators are specific and will change color only at a particular pH (H+ ion concentration).
Once you have determined if a substance is an acid or a base, you need to determine how strong (or concentrated) it is. The simplest measure of the strength of an acid or base is the concentration of H+ ion in the solution. The fastest way to determine pH is to use pH paper. It uses a broad range indicator to turns a series of colors from pH 1 to 14. The color change is then compared with a color chart to determine the pH. A high pH indicates a base, and a low pH indicates an acid. A pH near 7 indicates a neutral substance. Students should be aware that shampoos and soaps and most skin products are pH balanced near 7, to protect skin, hair and eyes.
