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History Sources Uses Hazards Facts Glossary Bibliography	By: Hilary Mill Valley Middle School "Chromium: the colorful side of gray"
Sources: Chromium, sometimes called chrome occurs only as a combined metal. It is usually found combined with iron and oxygen in a mineral called chromate.	Data Protons 24 Neutrons 28 Electrons 24 Atomic # 24 Atomic weight 51.996 Melts point 3398ºF Boiling point 4500ºF Classification Metal	Chromium is often used in paint.
History: Nicholas Vanquelin (1763-1829) was born a farm workers in Normandy, France. He worked as a France until 1777 he became apprentice to an apothecary in Rouen France. Then years later he moved to Paris were his ability was recognized. In a lead mineral called crocolite, he discovered chromium in 1797 naming it for the Greek "Chroma" Which means color. He named it that because so many of its compounds are brightly colored.		Facts: Chromium is used to make safes because of its strength. Rubies and emeralds get their color from chromium. Leather tanners use chromium. Chromium is used to color ceramic. Chromium dioxide is magnetic and is used for recording and video tapes Chromium melts at about 3398ºF Chromium boils at 4500ºF
Uses: Chromium resists corrosion. Chromium is also very shiny when polished. For these reasons it is used to coat. other metals. It is used to harden steel and make strong cutting tools. Alloys that have more than 10% chromium are called stainless steel that is used in the kitchen utensil and equipment. Lead chromate is a pigment used for paint. Some chromite is used in airline compasses to coat aluminum with thick , protective, oxide film. All life needs chromium. In humans it sometimes increases glucose tolerance and helps the action of insulin.		Hazards: Chromium is very irritable to the skin. Workers who handle much be protected. Breathing chromium dust leads to serious long problems. If skin is cut, contact with chromium leads to serious sorse. Cases of lung cancer have been observed in plants were chromate's are present.
Glossary: Chromium- A hard,brittle, gray metallic element. apothecary- a pharmacist chroma- Greek word for color corrosion- chemical process where substances, especially metals waste away to coat- plate alloys- combination of metals stainless steal- an alloy with more than 10% chromium glucose- sugar in your blood inslun- a hormone which helps the body use sugar and carbohydrates
Bibliography:   * Chemicool Periodic Table * Environmental Chemistry Periodic Table * Interactive Periodic Table of the Elements * Periodic Table * Periodic Table of the Elements * Periodic Table of Poetry * Pictorial Periodic Table * Web Elements Periodic Table   Images: http://www2.flamingtext.com/net-fu/job.cgi?job=050941757 www.anpac.com/AmericanNat/ more/chrome.jpg  www.dow.com/facilities/images/ terneuze/paint.jpg www.silversuperstore.com/extragraphics/ twiforks.jpg