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How did Sir Humphry Davy isolate sodium and potassium?

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Sir Humphry Davy isolated potassium and sodium in October 1807 by utilizing electrolysis, a process involving the interaction of electric currents with chemical compounds.12

Davy had theorized that chemical combinations occurred between substances of opposite electrical charges and reasoned that electrolysis provided the most effective means of decomposing compounds into their constituent elements. By employing a powerful battery to pass an electric current through their respective liquid compounds, he successfully freed these highly active metals for the first time. This pioneering work in electrochemistry demonstrated that electricity could be used to drive chemical reactions, a discovery that also led him to isolate other elements, including magnesium, calcium, strontium, and barium shortly thereafter.23