What Is Chromium Acetate?

Chromium acetate is a chemical compound produced by combining chromium metal with some form of acetate, or salt. Also known as chromous acetate, this compound is widely used in laboratory and scientific research settings, and also plays an important role in industry and manufacturing. Chromium acetate can be found in two basic forms, each of which offers its own distinct properties and applications.

This compound was first produced in 1844 by French chemist Eugene Peligot. Peligot later became widely known as the first person to isolate uranium molecules. While molecular research was limited during that time period, modern scientists recognize chromium acetate for its very strong quad-bond structure. This bond not only makes this compound very stable, but also makes it largely insoluble in water and other liquids. Each molecule consists of two chromium atoms, two water atoms and four acetate atoms.

Depending on how it is prepared and preserved, chromium acetate can be of the dihydrate or anhydrous variety. Dihydrate means that water is present in the molecule, while anhydrous means that no water is present. Dihydrate chromium acetate features a bright red color, while anhydrous varieties come in shades of blue, green, violet, and gray. Both come in powder, liquid, and paste-like textures.

Throughout history, some people have relied on tasteless, odorless compound as a folk medicine or home remedy for various ailments, though little solid research exists to support this type of application. Today, chromium acetate is widely used as a mordant, or tool to fix colored dyes in fabric. It can also be used in photo processing, where it helps to harden emulsion chemicals, or as a means of tanning leather. Perhaps the most common use for chromium acetate is in the laboratory, where this compound serves as a reducing agent or catalyst in a wide variety of scientific experiments.

The preparation of chromium acetate has long been a common project for chemistry students at schools and universities. This experiment is particularly valuable to organic chemistry students because it requires very precise control over oxygen levels, and also because it helps to illustrate the strength and importance of the quad-bond structure. As chromium reacts with acetic acid, it develops a bold blue or green hue. If too much oxygen is permitted to reach the compound, the blue transforms into a bright red coloring. Students who successfully complete this experiment will learn to control oxygen levels enough to prevent the solution from transitioning from blue to red.