Dichromates

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Dichromates

 

(also bichromates), salts of dichromic acid, H₂Cr₂O₇—for example, K₂Cr₂O₇. Most dichromates are orange-red. Usually they are more soluble than the corresponding chromates (salts of chromic acid, H₂CrO₄). Like chromates, dichromates are strong oxidizing agents in acid solution (hexavalent Cr is reduced to the trivalent state—for example, K₂Cr₂O₇ + 14HCl = 2KC1 + 2CrCl₃ + 3C1₂ + 7H₂O). A mixture of equal parts of a cold saturated solution of K₂Cr₂O₇ and concentrated H₂SO₄ (chromic mixture) has a very strong oxidizing action; it is used in the laboratory for cleaning chemical dishware.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.