electrolysis of conc. NaCl with mecury electrode

After electrolysis, pure sodium would not be sparated.

Instead, the sodium amalgam is treated with water to give sodium hydroxide solution and hydrogen gas. The equation is:
2Na/Hg + 2H2O → 2NaOH + H2 + Hg
or simply:
2Na + 2H2O → 2NaOH + H2

Therefore, the NaOH solution produced would not mixed with the brine solution, and the hydrogen produced would not mixed with the chlorine gas produced.
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