Rhodium's expensive, Rhodium is rare, it's on the metalic jewelry that you wear in your hair!

 

 

General Info
Rhodium is in the platinum family and is a transition metal.   It is number 45 on the Periodic Table and it’s symbol is Rh.  It is very rare and is the most expensive precious metal.  It is often used in alloys with platinum.  It can be highly toxic if inhaled but is harmless in solid form.

Properties
Rhodium is silvery white and metallic, it also has a high reflectance.  It’s melting point is 1964C and it’s boiling point is 3695C. It is not malleable.  It is very durable but has a lower density than platinum.  It has very low electrical contact.

History
An English man named William Hyde Wollaston discovered rhodium in 1803.  He discovered it by using a crude platinum ore; it appeared as a red powder as an alloy, mixed with some other elements.  The name came from the Greek word rhodon, meaning rose, it was named this because of the red colored powder it first appeared in. 

 

Occurrence
            Rhodium is often found in ores mixed with other elements such as palladium, silver, platinum, and gold.  The element can be found in South Africa, the Ural Mountains, and North America.  The main exporter of Rhodium is South Africa, followed by Russia.  Because it is so rare the annual world production of it is only about 25 tons.  Rhodium costs about $1,000 per ounce, eight times more than gold.  Besides being found naturally and mixed with other elements, Rhodium can also be extracted from used nuclear fuel.

Uses
Rhodium is used in catalytic converters, tools that convert harmful emissions from engines into less harmful gases.  It is also very useful to help resist corrosion and is often used in jewelry.  It can be used as an alloying agent, which makes palladium and platinum harder.  It also is used in electrical material because of its low electrical contact.

Isotopes
            The only naturally occurring isotope of Rhodium is 103Rh but it has many radioisotopes.  The most stable radioisotope it has is 101Rh with a 3.3-year half-life.  It’s primary decay product before 103Rh is ruthenium and the primary after product is palladium.

Symbol Half-Life
89Rh 10 months
95Rh 5.02 minutes
99Rh 16.1 days
100Rh 20.8 hours
103Rh Stable

 

 

 

Rhodium is a transition metal. Another transition metal is COBALT.

 

Glossary
 

malleable- able to be hammered or pressed permanently out of shape without breaking or cracking

catalytic converter- a device incorporated in the exhaust system of a motor vehicle, containing a catalyst for converting pollutant gases into less harmful ones

ore- a naturally occurring solid material from which a metal or valuable mineral can be profitably extracted

alloy- a metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion

isotope- each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element

corrosion- the process of corroding metal, stone, or other materials

 

 

Bibliography
  Emsley, John. Nature's Building Blocks. New york: Oxford, 2001.
Frank, David V., Beth Miaoulis, Griffith Jones, Steve Miller, John G. Little, and Jay M. Pasachoff. California Physical Science. Boston: Pearson Education, Inc., 2008.
"Isotopes of Rhodium." Wikipedia. 10 Feb. 2009 <http://en.wikipedia.org/wiki/Rhodium-103>.
"Rhodium: History." Nautilus. 10 Feb. 2009 <http://nautilus.fis.uc.pt/st2.5/scenes-e/elem/e04510.html>.
"Rhodium." Periodic Table of the Elements. 10 Feb. 2009 <http://periodic.lanl.gov/elements/45.html>.
"Rhodium." Wikipedia. 10 Feb. 2009 <http://en.wikipedia.org/wiki/Rhodium>.
Stwertka, Albert. A Guide to Elements. New York: Oxford, 1996.


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