Go to Home Page
Go to Education Section
You are here
Go to Directories Section
Go to Community Section
Go to Fun Section
Go to Science Store
Go to About PhysLink.com
Top Destinations Menu
 Ask the ExpertsAsk the
Experts

 Physics Job BoardPhysics
Job Board

 Physics and Astronomy Departments DirectoryUniversity
Departments

 FREE Einstein eCardsEinstein
eGreetings

 PhysLink.com Science eStoreScience
eStore


Local in California?
Visit one of our retail stores.
XUMP - Science Toys





Win an Apple iPod Touch 32GB! Or one of Einstein Stuff Packs worth over $50! Enter our Einstein Look-a-Like Photo Contest! Click here for more details.

Potassium
 Potassium 
K
Atomic Number: 19
Atomic Weight: 39.0983
Element Type: Alkali Metal
Crystal Structure: Cubic Face Centered
Melting Point: 63.38°C = 146.084°F = 336.53 K
Boiling Point: 759.0°C = 1398.2°F = 1032.15 K
Critical Temp: °C = °F = K
Atomic Radius: 2.77 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 2.03 Å
Electronegativity: 0.82

History

(English, potash - pot ashes; L.. kalium, Arab qali, alkali) Discovered in 1807 byDavy, who obtained it from caustic potash (KOH); this was the first metal isolated byelectrolysis.


Sources

The metal is the seventh most abundant and makes up about 2.4% by weight of the earth'scrust. Most potassium minerals are insoluble and the metal is obtained from them only withgreat difficulty.

Certain minerals, however, such as sylvite, carnallite, langbeinite, and polyhalite arefound in ancientlake and sea beds and form rather extensive deposits from which potassiumand its salts can readily be obtained. Potash is mined in Germany, New Mexico, California,Utah, and elsewhere. Large deposits of potash, found at a depth of some 3000 ft inSaskatchewan, promise to be important in coming years.

Potassium is also found in the ocean, but is present only in relatively small amounts,compared to sodium.



go to the top  
All rights reserved. © Copyright '1995-'2008 PhysLink.com
Win an Apple iPod Touch 32GB! Or one of Einstein Stuff Packs worth over $50! Enter our Einstein Look-a-Like Photo Contest! Click here for more details.