Indikaattoriväri

Indikaattoriväri refers to a substance that changes color in response to a specific chemical change. These color changes are typically visually apparent and are used to indicate the presence or absence of a particular substance, or to signal a change in conditions such as pH.

The most common application of indicator dyes is in acid-base titrations. For example, litmus paper turns red in acidic solutions and blue in alkaline solutions. Phenolphthalein, another well-known indicator, is colorless in acidic solutions but turns pink in alkaline solutions. The precise pH range over which an indicator changes color is known as its transition range. Different indicators have different transition ranges, allowing chemists to select the most appropriate indicator for a particular titration to ensure a sharp and easily detectable color change at the equivalence point.

Beyond titrations, indicator dyes have various other uses. They can be incorporated into test strips for quick qualitative analysis, such as determining the pH of water or urine. Some indicator dyes are also used in environmental monitoring to detect pollutants or changes in water quality. In some biological and medical applications, indicator dyes are used to visualize specific cellular structures or processes. The principle remains the same: a discernible color shift signals a specific chemical event.