Cadmium

By: Jeremy Willett

History• Its name is derived from the Latin

cadmia and the Greek kadmeia• First discovered by Friedrich

Strohmeyer, a German chemist, in 1817.

• While studying calamine(ZnCO3), it was noticed that when heated some samples glowed yellow while others did not.

• After later examination, he concluded that the calamine that changed color contained a new element, Cadmium

Properties

• Atomic Number: 48• Atomic Weight: 112.411• Melting Point: 594.22 K (321.07°C or 609.93°F)• Boiling Point: 1040 K (767°C or 1413°F)• Density: 8.69 grams per cubic centimeter• Phase at Room Temperature: Solid• Element Classification: Metal• PeriodNumber:5 GroupNumber:12

Major Isotopes• Nine major radioactive isotopes of

cadmium exist, of which only three – cadmium-109, cadmium-113, and cadmium-113m– have half-lives long enough to warrant potential concern. The half-lives of the other six are less than 45 days.

• There are 5 stable isotopesCadmium 108 Cadmium

110Cadmium 111 Cadmium

112Cadmium 114

Uses

• Most in the U.S. used in nickel-cadmium batteries

• Also used as an anticorrosive coating for steel and cast iron, and used as component of certain specialty alloys.

• Used in semiconductors (such as cadmium selenide and telluride), in dyes and pigments, as a stabilizer in plastics such as polyvinyl chloride, and as a neutron absorber in nuclear reactor control rods and shields.

Concerns• Cadmium has negative effects on

human health• In the human body, cadmium

accumulates mainly in the kidneys. At high levels, it can reach a critical threshold and can lead to serious kidney failure.

• Cadmium is generally taken into the body through smoking as well as trace amount sin food and water which has came from the soil.

• Cadmium intake by the general population has decreased in the past 60 years.

Availability• Cadmium is found in rare ores such as sphalerite

and greenockite, and it is formed as a byproduct during production of zinc, copper, and lead.

• The United States is among the top ten producers, refining over 1,000 metric tons of cadmium a year.

Miscellaneous

• Isolating cadmium consists of the following series of reactions.

ZnO + C → Zn + COZnO + CO → Zn + CO2

CO2 + C → 2CO• Cadmium is an extremely toxic

metal, which is why it has its negative effects on the human body.

Sources

• http://periodictable.com/Samples/048.12/index.s12.html• http://education.jlab.org/itselemental/ele048.html• http://www.ead.anl.gov/pub/doc/cadmium.pdf• http://www.webelements.com/cadmium/history.html• http://www.cadmium.org/• http://www.tech-faq.com/nickel-cadmium-battery.html• http://www.chemicalelements.com/elements/cd.html• http://library.thinkquest.org/08aug/01930/commonmetals/C

admium.html• http://chemistry.about.com/od/famouschemists/p/friedrichst

romeyerbio.htm• http://www.mineralatlas.com/australian_minerals/tasmania5

.htm