Potassium is a chemical element wi seembol K (derived frae Neo-Latin, kalium) an atomic nummer19. It wis first isolate frae potash, the ess o plants, frae whilk its name derives. In the periodic cairt, potassium is ane o the alkali metals. Aw o the alkali metals hae a single valence electron in the ooter electron shell, whilk is easy remuived tae creaut an ion wi a positive chairge – a cation, whilk combines wi anions tae form sauts. Potassium in naitur occurs anly in ionic sauts. Elemental potassium is a saft sillery-white alkali metal that oxidizes rapidly in air an reacts vigorously wi watter, generatin sufficient heat tae ignite hydrogen emittit in the reaction an burnin wi a lilac-colored flame. It is foond dissolved in sea watter (which is 0.04% potassium bi wecht^[4][5]), an is pairt o mony meenerals.

Naiturally occurrin potassium is componed o three isotopes, o whilk ⁴⁰
K is radioactive. Traces o ⁴⁰
K are foond in aw potassium, an it is the maist common radioisotope in the human bouk.

Potassium is chemically gey seemilar tae sodium, the previous element in group 1 o the periodic table. Thay hae a seemilar first ionisation energy, whilk allous for ilka atom tae gie up its sole outer electron. That thay are different elements that combine wi the same anions tae mak seemilar salts wis suspected in 1702,^[6] an wis proven in 1807 uisin electrolysis.

Maist industrial applications o potassium exploits the heich solubility in watter o potassium compoonds, sic as potassium saips. Hivy crop production rapidly depletes the sile o potassium, an this can be remedied wi agricultural fertilizers containin potassium, accoontin for 95% o global potassium chemical production.^[7]

Potassium ions is necessar for the function o aw livin cells. The transfer o potassium ions throu nerve cell membranes is necessar for normal nerve transmission; potassium depletion can result in numerous abnormalities, includin an abnormal hert rhythm an various electrocardiographic (ECG) abnormalities. Fresh fruits an vegetables is guid dietar soorces o potassium. The body responds tae the influx o dietar potassium, whilk raises serum potassium levels, wi a shift o potassium frae ootside tae inside cells an an increase in potassium excretion bi the neers.

Citit soorces

• Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN0-08-037941-9.