Bromothymol blue sodium salt is widely used as a pH indicator in various scientific and industrial applications. It is particularly effective in determining pH levels in the range of 6.0 to 7.6, where it transitions from yellow (acidic) to blue (basic). This property makes it valuable in laboratory experiments for monitoring pH changes in chemical reactions, especially in biology and chemistry studies. It is also employed in aquariums and aquatic research to assess water quality and ensure optimal conditions for aquatic life. Additionally, it is used in educational settings to demonstrate acid-base titration processes, helping students visually understand pH shifts. In microbiology, it serves as an indicator in culture media to detect metabolic activities of microorganisms based on pH changes. Its stability and distinct color change make it a reliable tool for pH monitoring in diverse applications.