Chrome alum

Chrome Alum is a chemical compound that is classified as a type of alum. It is also known as Chromium(III) potassium sulfate and is commonly used in the process of tanning leather and in some types of photography.

Chemical Composition

Chrome alum is a double sulfate of chromium and potassium. Its chemical formula is KCr(SO4)2·12(H2O). The compound is a deep violet in color due to the presence of chromium. It forms large octahedral crystals and is highly soluble in water.

Uses

Chrome alum is used in various industries due to its unique properties. It is used in the leather industry for tanning, where it helps to cross-link the collagen fibers, increasing the thermal stability and shrinkage temperature of the leather.

In photography, chrome alum is used as a hardening agent in the process of making gelatin emulsions. It is also used in the process of dyeing fabrics, in the manufacturing of ceramics and glass, and in the treatment of water.

Safety

While chrome alum is not considered highly toxic, it can cause irritation if it comes into contact with the skin or eyes. It is recommended to handle it with care and use appropriate safety equipment.

See Also

• Alum
• Chromium
• Potassium sulfate
• Leather tanning
• Photography