There is a marked difference in their colour. However, the two are quite different from each other. Therefore, both are oxoanions of chromium. Lewis structure of Chromate What is the Difference between Chromate and Dichromate?Ĭhromate and dichromate are two different anions containing the same elements– chromium and oxygen. The following image depicts the Lewis structure of a chromate ion. Two oxygen atoms carry a -1 charge on them. There are four oxygen atoms and a chromium atom. The anion has two single covalent bonds and two double covalent bonds. The Lewis structure of the chromate ion shows its bonding and non-bonding electrons. The anion has a minus two negative charge. This structure has one chromium atom and four oxygen atoms. Chromate chemical formula/ chromate symbol: CrO 4 2.IUPAC name of chromate: dioxido(dioxo)chromium.

The most widely used chromate salts are potassium and sodium salts. The salts of chromic acid containing the chromate anion usually have an intense yellow colour.

The chromium oxoanion formed from chromic acid is called chromate. It also acts as a substrate to ensure improved paint adherence on nonferrous surfaces. Chromate conversion coating imparts brightness and enhances the corrosion resistance of bare metals. As an oxidizing agent, it finds application in various industries. It is a chromium oxoanion that is formed by the removal of two protons from chromic acid. An atom of chromium and four of oxygen combine to give chromate.

Chromium charge in dicromate