Used as a mixed acid-base indicator in titrations, particularly for detecting the endpoint in the titration of strong acids with strong bases where a sharp pH change occurs around neutrality. The combination provides a clear color transition from red (acidic) through green (neutral) to blue (basic), making it effective for applications requiring visual pH detection in the range of approximately pH 4.0 to 7.6. Commonly employed in educational labs and water quality testing to demonstrate pH changes and determine alkalinity or acidity in solutions.