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Potassium Element in Periodic Table | Atomic Number Atomic Mass


Potassium Element:

Potassium is an element in the first group of periodic table and its symbol is K, derived from the Latin word Kalium. The atomic number of potassium is 19. The first group of periodic table contains alkali metals. Since all alkali metals have a single electron in their outermost shell, K too has a single electron in its peripheral orbital. Hence, K  possesses valency one and it tends to donate electron readily to gain stable noble gas configuration. It is more reactive than its predecessors in the Group I (Lithium and Sodium). When exposed to air, it catches fire violently by reacting with oxygen present in the air.Like sodium, K  is also a soft metal which can be cut with a knife.For avoiding getting ablaze or exploded, pure K is preserved in kerosene. Water is not suitable for preservation of K because it reacts with water readily, liberating hydrogen accompanied by heat and forming potassium hydroxide.

Similar to the other elements in the group I of periodic table, K is electropositive and it has a tendency to gain stable electronic configuration of the noble element Argon present in the same period. It is an electropositive element like the other alkali metals in the group I of periodic table.

Potassium Element Uses:

Potassium, being a highly reactive element, is used mainly in its combined forms or its compounds.

  1. It  is the most essential component in fertilizers. The demand for fertilizers containing K is so large across the world that potassium is used in huge quantities for utilizing in agriculture, horticulture and hydroponics (a special type of growing plants sans soil ).
  2. It  is also used in culinary additives such as baking powder which has Potassium sodium tartrate (KNaC4H4O6, Rochelle salt) as its main ingredient.  Rochelle salt is also used in silvering of mirrors.
  3. Potassium cyanide is a good solvent for dissolving precious metals like gold, silver etc.
  4. Potassium hydroxide, Potassium nitrate are widely used in industries as reagents on large scale.
  5. Potassium chlorate KClO3 is used in preparation of safety matches and explosives.
  6. Potassium chromate K2Cr2O4 is used in preparation of inks, dyes, stains and in manufacture of colorfully burning fireworks, in tanning of leather etc., though the presence of chromium atoms is partly responsible for the uses.


Potassium Element Information:

Discovery year: 1807

Discovered by: Humphry Davy

Atomic number: 19

Relative atomic mass: 39.098 

Electron configuration: [Ar] 4s1

Block: s-block

Other elements in the same block:

Hydrogen, Helium, Lithium, Beryllium, Sodium, Magnesium, Calcium, Rubidium, Strontium, Caesium, Barium, francium and Radium are other elements in the s-block.

Period: period 4

Other elements in the same period:

Calcium, Scandium, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Gallium, Germanium, Arsenic, Selenium, Bromine and Krypton.

Group: group 1 (alkali metals)

Other elements in the same group:

Hydrogen, Lithium, Sodium, Rubidium, Caesium and   francium

Other elements in the same orbital:

Calcium is the element in the same group.

Allotropes: none

Key isotopes: 39

Melting point: 63.5°C, 146.3°F, 336.7 K

Boiling point: 759°C, 1398°F, 1032 K

Element category: alkali metal

Density (g cm−3): 0.89

CAS number: 7440-09-7

Color: silvery gray

You can know detailed information for each element,

Hydrogen, HeliumLithiumBerylliumBoronCarbonNitrogenOxygenFluorine,  Neon , SodiumMagnesiumAluminiumSiliconPhosphorusSulfurChlorineArgon, PotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseIronCobaltNickelCopperZincGalliumGermaniumArsenicSeleniumBromine, Krypton,  Rubidium, StrontiumYttriumZirconiumNiobiumMolybdenumTechnetiumRutheniumRhodiumPalladiumSilverCadmiumIndiumTinAntimonyTelluriumIodine, Xenon,  Caesium, BariumLanthanum,  CeriumPraseodymiumNeodymiumPromethiumSamariumEuropiumGadoliniumTerbiumDysprosiumHolmiumErbiumThuliumYtterbiumLutetiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGoldMercuryThalliumLeadBismuthPoloniumAstatine, Radon,  Francium, RadiumActiniumThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrenciumRutherfordiumDubniumSeaborgiumBohriumHassiumMeitneriumDarmstadtiumRoentgeniumCoperniciumNihoniumFleroviumMoscoviumLivermoriumTennessine, Oganesson.

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