Louis-Nicholas Vauquelin discovered it in 1797. It has to make chromium from chromite by taking the chromite and treating it with molten alkali and oxygen, converting the chromium to alkali chromate and the latter is dissolved in water and precipitated as sodium dichromate which is then reduced with carbon to chromium oxide and the oxide is then reduced with aluminum to make chromium metal. The number of protons in chromium is 24, number of electrons is 24 and the number of neutrons is 28. The boiling point of chromium is 3,434 degrees F, the melting point of chromium is 4,500 degrees F and since chromium is a metal, it has no freezing point. Chromium forms oxygen compounds such as chromium oxide or chromic acid.
Chromic acid can react violently with some organic materials.
Chromatic acid gradually liquefies when it is exposed to moist air. Chromite ore is mostly abundant in the earth's crust. Copyright 1997-2001 and Disclaimer for the San Juan Unified School District. All Rights Reserved.