Home > Product list > K


Potassium , including Technical Data, Safety Data and its high purity propertiesresearch, applications and other useful facts are discussed below. Scientific facts such as the atomic structure,ionization energyabundance on Earthconductivity and thermal properties are included. 

Potassium is the seventh most abundant element on earth. In its metallic form it is one of the most reactive and electropositive of all metals and rapidly oxidizes. As with other metals of the alkali group, the metal decomposes in water with the evolution of hydrogen. It catches fire spontaneously in water. In high purity, potassium compounds have numerous pharmacological, medical, and electronics applications. Important compounds include the hydroxide, nitrate, carbonate, chloride, bromide, iodide, and sulfate. Lower purity compounds are used in pyrotechnics for its violet color on ignition and in glass and ceramic glazes to produce this color. Potassium also used as a nutrient in plant growth. 

Potassium facts, including appearance, CAS #, and molecular formula and safety data, research and properties are available for many specific states, forms and shapes on the product pages listed to the left. Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Nanoparticles and nanopowders provide ultra high surface area which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits. 

Oxides are available in forms including powders and dense pellets for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Potassium is available in soluble forms including chlorides, nitrates and acetates. These compounds are also manufactured as solutions at specified stoichiometries. 

Potassium is a Block S, Group 1, Period 4 element. The number of electrons in each of Potassium‘s shells is 2, 8, 8, 1 and its electronic configuration is [Ar] 4s1. In its elemental form potassium‘s CAS number is 7440-09-7. The potassium atom has a radius of 227.2 .pm and it‘s Van der Waals radius is Potassium is not toxic. 

All elemental metals, compounds and solutions may be synthesized in ultra high purity (e.g. 99.999%) for laboratory standards, advanced electronic, thin fillm deposition using sputtering targets and evaporation materials, metallurgy and optical materials and other high technology applications. Information is provided for stable (non-radioactive) isotopesOrgano-Metallic Potassium compounds are soluble in organic or non-aqueous solvents. See Analytical Services for information on available certified chemical and physical analysis techniques including MS-ICP, X-Ray Diffraction, PSD and Surface Area (BET) analysis. 

Since potassium reacts violently with water, it only occurs in nature in ionic salts. Potassium was first discovered by Sir Humphrey Davy in 1807. The origin of the element name comes from the English word ‘potash‘ meaning pot ashes and the Arabic word ‘qali‘ which means alkali. The symbol K originates from the Latin word ‘kalium‘.

Abundance. The following table shows the abundance of potassium and each of its naturally occurringisotopes on Earth along with the atomic mass for each isotope.
Isotope Atomic Mass % Abundance on Earth
K-39 38.9637068 93.26
K-40 39.9639987 0.01
K-41 40.9618260 6.73

The following table shows the abundance of Potassium present in the human body and in the universe scaled to parts per billion (ppb) by weight and by atom:
  Typical Human Body Universe
by Weight 2000000 ppb 3000 ppb
by Atom 320000 ppb 100 ppb

Safety Data and Biological Role. The safety data for potassium metalnanoparticles and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the left margin. Potassium compounds play an important biological role. The potassium cation is the major cation in intracellular fluids and is essential for nerve and heart function. 

Ionization Energy. The ionization energy for potassium (the least required energy to release a single electron from the atom in it‘s ground state in the gas phase) is stated in the following table:
1st Ionization Energy 418.81 kJ mol-1
2nd Ionization Energy 3051.85 kJ mol-1
3rd Ionization Energy 4419.64 kJ mol-1

Conductivity. As to potassium‘s electrical and thermal conductivity, the electrical conductivity measured as to electrical resistivity @ 20 ?C is 6.15 μΩcm and its electronegativities (or its ability to draw electrons relative to other elements) is 0.82. The thermal conductivity of potassium is 102 W m-1 K-1. 

Thermal Properties. The melting point and boiling point for potassium are stated below. The following chart sets forth the heat of fusion, heat of vaporization and heat of atomization.
Heat of Fusion 2.4 kJ mol-1
Heat of Vaporization 79.1 kJ mol-1
Heat of Atomization 90.14 kJ mol-1

Formula Atomic Number Molecular Weight Electronegativity (Pauling) Density Melting Point Boiling Point Vanderwaals radius Ionic radius Energy of first ionization
K 19 39.0983 g.mol-1 0.8 0.86 at 0 °C 63.2 °C 760 °C 0.133 (+1) nm 418.81 kJ.mol-1