What is Potassium dichromate?
[[File:Potassium-dichromate-sample.jpg|thumb|Potassium dichromate]] '''Potassium dichromate''' is a [[chemical compound]]. It contains [[potassium]] and [[dichromate]] [[ion]]s. It has a chemical formula of K<sub>2</sub>Cr<sub>2</sub>O<sub>7 (K2Cr)</sub>. The [[chromium]] is in its +6 [[oxidation state]]. ==Properties== It is a bright red [[crystalline]] solid. It is a strong [[oxidizing agent]] in [[acid]]ic conditions. It is poisonous because it contains [[dichromate]], which is [[carcinogen]]ic. It can be destroyed by reaction with [[reducing agent]]s. It can be reduced to green chromium(III) compounds such as [[chromium(III) oxide]]. ==Preparation== Potassium dichromate can be made by oxidation of potassium hydroxide and chromium(III) oxide. It can also be made by adding an acid to [[potassium chromate]]. ==Occurrence== It is very rarely found in the earth. It is only found in very dry areas. If it rains, it dissolves in the water and is washed away. ==Uses== It is used as a [[reagent]] for many chemicals, such as [[alcohol]]. Some breath alcohol testers use this, and the red turns to green when there is alcohol in the breath. It can be used to make [[chromic acid]], which is used to clean glass. It can be used in [[cement]]. It is used to [[tanning|tan]] [[leather]]. It can be used in [[photography]] and to test for certain [[metal]]s. It can be used to treat wood. ==Safety== Potassium dichromate is very irritating. It can cause cancer when the dust is inhaled. It is a strong oxidizing agent and can start fires. It can be reacted with [[iron(II) sulfate]] to detoxify (remove the [[toxic]]ity of) it. ==Related pages== *[[Potassium chromate]] *[[Ammonium dichromate]] *[[Chromate]] [[Category:Potassium compounds]] [[Category:Chromium compounds]]