How can I extract sodium and chloride from salt?

1 Answer
May 16, 2015

You can't do it at home, but sodium and chlorine are obtained commercially by passing an electric current through molten salt.

Salt melts at 801 °C, chlorine is a poisonous gas, and molten sodium is extremely reactive.

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The "Na"^+Na+ ions are reduced at the cathode:

"Na"^+"(l)" + "e"^(-) → "Na(l)"Na+(l)+eNa(l)

Liquid sodium floats to the top and is drained off into a storage tank.

The "Cl"^-Cl ions are oxidized at the anode.

"2Cl"^(-)"(l) "→ "Cl"_2"(g)" + 2"e"^(-) 2Cl(l) Cl2(g)+2e

The chlorine gas bubbles out of the molten salt above the anode