What is "sodium dichromate"

n. a red-orange salt used as a mordant [syn: sodium bichromate]

Sodium dichromate is the inorganic compound with the formula Na Cr O. Usually, however, the salt is handled as its dihydrate NaCrO·2 HO. Virtually all chromium ore is processed via conversion to sodium dichromate and virtually all compounds and materials based on chromium are prepared from this salt. In terms of reactivity and appearance, sodium dichromate and potassium dichromate are very similar. The sodium salt is, however, around twenty times more soluble in water than the potassium salt (49 g/L at 0 °C) and its equivalent weight is also lower, which is often desirable.