Titan yellow (also known as Clayton yellow, Thiazole Yellow G, or C.I. 19540) is a triazene dye used as a pH indicator and stain in microscopy.

 Titan yellow (also known as Clayton yellow, Thiazole Yellow G, or C.I. 19540) is a triazene dye used as a pH indicator and stain in microscopy. It's a yellow-brown powder with a pH value of 5.1 and a melting point above 300°C. In basic solutions (pH 12-13), it turns from yellow to orange. 

Key Features:

pH Indicator:

Titan yellow changes color based on the pH of the solution. It's yellow in acidic environments and turns orange in basic environments. 

Triazene Dye:

It belongs to the triazene dye family, a class of compounds known for their color and staining properties. 

Applications:

Analytical Reagent: Used for colorimetric determination of various compounds. 

Microscopy: Stain and fluorescent indicator in microscopy, particularly for biological samples. 

Dyeing: Used for dyeing cotton, viscose rayon, and natural silk. 

Physical Properties:

Appearance: Yellowish brown powder. 

Melting Point: >300°C (decomposition). 

pH Value: 5.1 (at 10 g/l in water at 20°C). 

Solubility: 29 g/l at 20°C. 

Safety Information:

Storage: Store at +2°C to +30°C.

WGK: WGK 3 - highly hazardous to water.

Storage Class: 10 - 13 Other liquids and solids. 

Other Names:

Clayton yellow .

Thiazole Yellow G .

Naphthamine G .