By Sydney Reiff
The element is used to harden steel and other metals so it has a very low reactivity. It is mostly only flammable as a powder.
Chromium has an atomic number of 24 and a mass of 52. This means that there is 24 protons and 28 neutrons inside the nucleus and there is 24 electrons circling it.
It is the first element in group 6 and that is the 4th column from the left.
Chromium comes from the Greek word chroma meaning colorful. The green coloration of emeralds is due to chromium.
Chromium was first discovered by a French Chemist named Nicholas Louis Vanquelin in Paris, 1798. Vanquelin was intrigued by a red mineral that was discovered in a gold mine (Siberian red lead) so he dissolved it in acid and precipitated the lead. Then he examined what was left and decided that he had isolated chromium. The Siberian red lead (crocoite) is a form of lead chromite.
Chromium has a few very useful isotopes. Cr-50 is used to produce radioisotope Cr-51 which is used to measure blood volume and red blood survival. Cr-53 and Cr-54 are used to study chromium metabolism and adult diabetes
-lead chromate/chrome yellow: a yellow pigment in paint
-chromic oxide/chrome green: the 9th most abundant compound in the Earth’s crust, also used as a green pigment in paint
-potassium dichromate is used to tan leather
- Element Card: Gray, Theodore W. (2008). The Photographic Card Deck of the Elements.
- Elements Book: Gray, Theodore W. (2009). The Elements: A visual exploration of every known atom in the universe. New York: Black Dog & Leventhal Publishers, Inc.
- Royal Society of Chemistry Periodic Table: http://www.rsc.org/periodic-table
- Los Alamos National Lab Periodic Table: http://periodic.lanl.gov/24.shtml
- Chromium Isotopes: http://www.tracesciences.com/cr.htm