Potassium Periodic Table

Potassium is the 19 th element on the periodic table. It is located in period 4 and group 1. In other words, it is the element in the first column of the table that begins the fourth row.

Us speed test. Seventeen isotopes of potassium are known. Ordinary potassium is composed of three isotopes, one of which is 40°K (0.0118%), a radioactive isotope with a half-life of 1.28 x 10 9 years. Element 19 of Periodic table is Potassium with atomic number 19, atomic weight 39.0983. Potassium, symbol K, has a Body Centered Cubic structure and Silver color. Potassium is a alkali metal element. Periodic Table of Elements - The periodic table is a very useful listing of all 118 elements by symbol, atomic number, and atomic mass and molecular mass. Elements with similar chemical properties are called groups. Visit BYJUS to learn more about it. The periodic table is arranged by increasing: atomic number Rather than numbering groups 1-18, another method of organization has been to number the transition metals separately (with the letter B) from the groups on the left and right sides on the periodic table (with the letter A).

Atomic Number:19
Atomic Symbol:K
Atomic Weight:39.098
Electron Configuration:[Ar]4s1
Total Isotopes28
Total Isomers4
Radioactive Isotopes22
Stable Isotopes2
X-Ray Energies

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

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

Certain minerals, however, such as sylvite, carnallite, langbeinite, and polyhalite are found in ancientlake and sea beds and form rather extensive deposits from which potassium and 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 in Saskatchewan, promise to be important in coming years.

Potassium periodic table protons

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


Potassium is never found free in nature, but is obtained by electrolysis of the hydroxide, much in the same manner as prepared by Davy. Thermal methods also are commonly used to produce potassium (such as by reduction of potassium compounds with CaC2, C, Si, or Na).


The greatest demand for potash has been in its use for fertilizers. Potassium is an essential constituent for plant growth and is found in most soils.

An alloy of sodium and potassium (NaK) is used as a heat-transfer medium. Many potassium salts are of utmost importance, including the hydroxide, nitrate, carbonate, chloride, chlorate, bromide, iodide, cyanide, sulfate, chromate, and dichromate.


It is one of the most reactive and electropositive of metals. Except for lithium, it is the lightest known metal. It is soft, easily cut with a knife, and is silvery in appearance immediately after a fresh surface is exposed. It rapidly oxidizes in air and must be preserved in a mineral oil such as kerosene.

Potassium Periodic Table Facts

Potassium periodic table info

As with other metals of the alkali group, it decomposes in water with the evolution of hydrogen. It catches fire spontaneously on water. Potassium and its salts impart a violet color to flames.

Potassium Periodic Table Group


Seventeen isotopes of potassium are known. Ordinary potassium is composed of three isotopes, one of which is 40oK (0.0118%), a radioactive isotope with a half-life of 1.28 x 109 years.


The radioactivity presents no appreciable hazard.


Metallic potassium is available commercially for about $40/lb in small quantities.