Тимолфталеин

Thymolphthalein 1.Photo: 2.Properties:White or straw yellow powder,insolve in water,solve in alcohol. 3. Molecular FormulaC28H30O4Molecular Weight430.54PH change range9.3 ( colorless)-- 10.5(blue)Solubility in ethanolPasses testSulfated ash,percent≤1Solubility in sodium hydroxidePasses testMelting range251.0--255.0 oC 4.Describe: 1).Thymolphthalein is an acid-base (pH) indicator. Its transition range is at approximately pH 9.3-10.5. Below this pH, it is colorless; above this pH, it is blue. The molar extinction coefficient for the blue thymolphthalein dianion is 38000 M-1cm-1 at 595 nm. 2).It can be used to make a disappearing ink. Dissolve the thymolphthalein in alcohol solution and add sodium hydroxide (NaOH) dropwise until it turns blue. It can then be sprayed onto cloth. After several minutes, it will turn colorless. (Carbon dioxide from the air will react with the basic solution. When the pH drops below 9.3, the thymolphthalein turns colorless.) Such inscription can be turned visible again by submerging it in liquid of pH higher than 10.5. A similar pH indicator is phenolphthalein, which is colorless in acidic and neutral pH ranges and bright fuchsia at high (basic) pH. 5.Kindly note:We are the only manufacturer for this prodcut in China.