Alkali

late 14c., "soda ash," from Medieval Latin alkali, from Arabic al-qaliy "the ashes, burnt ashes" (of saltwort, which abounds in soda due to growing in alkaline soils), from qala "to roast in a pan." Later extended to similar substances, natural or manufactured. The modern chemistry sense is from 1813.

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Potassium

metallic element, 1807, coined by English chemist Sir Humphrey Davy from Modern Latin potassa, Latinized form of potash (q.v.). Davy first isolated it from potash. Symbol K is from Latin kalium "potash," from Arabic al-qaliy "the ashes, burnt ashes" (see alkali).

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