Cresol Red, a well-established pH indicator, offers a fascinating study in chemical properties and practical applications. Identified by its CAS number 62625-29-0, this sulfonphthalein derivative, with the molecular formula C21H19NaO5S, is a cornerstone in many scientific endeavors requiring precise pH measurement. Its characteristic brown powder appearance and solubility in common solvents like water and ethanol make it easy to handle and prepare for laboratory use. Understanding these basic Cresol Red chemical properties is the first step in appreciating its utility.

The core functionality of Cresol Red lies in its behavior as an acid-base indicator. It exhibits two distinct pH transition intervals. In the lower range, approximately pH 0.2 to 1.8, it transitions from a red hue to yellow. Subsequently, in the higher range, from about pH 7.2 to 8.8, it shifts from yellow back to red. This dual-range capability makes it particularly useful for titrations where the equivalence point falls within these pH values, providing clear visual cues for the analyst. Knowledge of the specific Cresol Red pH indicator range is crucial for selecting it for a given application.

The versatility of Cresol Red extends beyond traditional analytical chemistry. Its thermochromic properties, meaning its ability to change color with temperature, have led to its integration into thermochromic materials. These materials have applications ranging from novelty items to more technical uses in temperature sensing. Additionally, Cresol Red plays a role in the cosmetic industry, where its colorimetric properties can be leveraged in product formulations. The extensive range of Cresol Red applications highlights its broad utility.

In the pharmaceutical sector, Cresol Red serves a specific yet important function: measuring the hydrophobicity of therapeutic drugs. This characteristic is critical for understanding how a drug will interact within the body, affecting its absorption, distribution, metabolism, and excretion. By quantifying drug hydrophobicity, researchers can optimize drug formulations and predict their pharmacokinetic profiles. This demonstrates a sophisticated use of Cresol Red chemical properties in medical science.

For laboratories and research institutions, the accessibility and reliability of Cresol Red are key advantages. Many suppliers offer it, and the process of buying Cresol Red online is straightforward for those needing consistent laboratory supplies. The extensive documentation available, including details on its Cresol Red CAS number, ensures researchers have all the necessary information for proper use and compliance.

In conclusion, Cresol Red is a compound of significant chemical interest and practical value. Its predictable color changes, coupled with its applications in diverse fields such as analytical chemistry, material science, cosmetics, and pharmaceuticals, solidify its importance. By thoroughly understanding its chemical properties and the specific pH ranges it indicates, scientists can effectively leverage Cresol Red to achieve accurate and meaningful results in their work.