1. Chromium

2. Discovery of Chromium
In 1797, Louis-Nicholas Vauquelin discovered Chromium while experimenting with Siberian red lead.
He mixed crocoite with hydrochloric acid (HCl) to yield chromium oxide (CrO3).
In 1798, he was surprised to obtain metallic chromium by heating chromium oxide in a charcoal oven because he believed that a method to isolate chromium didn’t exist yet.
Today, one can yield chromium by heating the mineral chromite (FeCr2O4) in the presence of silicon or aluminum.

3. + = Discovery of Chromium (cont) Chromite Heated in oven Chromium
(with aluminum or silicon)

4. Characteristics of Chromium
Steel-gray color
Lustrous
Hard metal
High Melting Point (1907 °C)
High Boiling Point (2671 °C )
Odorless
Tasteless
Somewhat Malleable
Hmmm… Chromium has no taste or smell.

5. Sources of Chromium Formed from the ore “Chromite”
Found in Zimbabwe, Russia, New Zealand, Turkey, Iran, Albania, Finland, Democratic Republic of Madagascar, and the Phillippines.

6. Sources of Chromium (cont)
= places Chromite can be found

7. Uses of Chromium Chromium is used to: Harden Steel
Manufacture Stainless Steel
Form Many Useful Alloys
Produce a Hard, Beautiful Surface
Prevent Corrosion
Gives Glass an Emerald Green Color
Used as a Catalyst.
(the refractory industries use Chromite for forming bricks)

8. Bohr-Rutherford Diagram
Yep! That’s our model!

9. Bibliography Jefferson Lab. Accessed 01/12/07.
1. Wikipedia, The Free Encyclopedia. Accessed 01/09/07.
Web Elements. Accessed 01/12/07.
Jefferson Lab. Accessed 01/12/07.

10. Many thanks to Elton John for providing me with his song “El Dorado.”