Thymolphthalein

Thymolphthalein is a chemical compound used as an indicator in acid-base titrations. It is a colorless crystalline solid that is soluble in ethanol and slightly soluble in water. The compound is a derivative of phthalein, with a thymol group attached to the phthalic acid. Thymolphthalein is commonly used in laboratories for its ability to change color in response to changes in pH. In acidic solutions, thymolphthalein remains colorless. However, when the pH of the solution exceeds 10.5, it turns a vivid pink or magenta color. This color change makes it useful for determining the endpoint in titrations involving strong bases and weak acids. The compound is also used in the preparation of other indicators and as a pH indicator in various applications. Thymolphthalein is generally considered safe for laboratory use, but like all chemicals, it should be handled with care to avoid skin and eye contact.