Potassium

From Anvita Health Wiki

Contents 1 Introduction 2 Occurrence 3 Characteristics 4 Uses 5 More General Terms 6 Additional Terms 7 Internet Database 8 References

Introduction

• From the English potash. The symbol K comes from the Latin kalium meaning alkali. Isolated in 1807 by Sir Humphrey Davy.

Occurrence

• 7th most abundant metal
• occurs abundantly in nature esp combined in minerals
• never found free in nature
• found in most soils

Characteristics

• silver-white soft light low-melting univalent metallic element of the alkali metal group
• 2nd least dense metal (after lithium)
• oxidizes very rapidly in air
• must be stored under argon or mineral oil
• potassium & its salts impart a lilac color to flames
• reacts with water

• K + H2O -> K+ + OH- + H2 + heat
• the heat generally ignites the H2 (in the presence of O2)

Uses

• metal rarely used
• salts of K+ used in

• fertilizers
• match heads
• glass
• soaps
• detergents

• [40]K isotope is used to date rocks

More General Terms

• alkali metal

Additional Terms

• K+
• periodic table

Internet Database

PubChem: 814
PubChem: 813

References

1. Webster's Ninth New Collegiate Dictionary, Miriam- Webster Inc. Springfield, MA 1990
2. Chemical & Engineering News, Sept 8, 2003

potassium [K, kalium]