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What is the boiling point of vodka?

I have found the boiling point of ethanol, ~173 (degrees) F.

However, I am unable to find the boiling point of vodka. I found some information on it, but I do not trust the source.

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    $\begingroup$ This question is fairly imprecise. It is sensible to discuss the boiling points of water/ethanol mixtures versus composition, but said composition will differ from between the vapor and liquid phases, with enrichment in the lower boiling component. The presence of the azeotrope mentioned in Spiessbuerger's answer complicates the matter slightly, but that azeotropic composition is so close to pure ethanol, this forms a decent quick guess. Generally these curves are not linear for any distillation. $\endgroup$
    – Lighthart
    Sep 3, 2014 at 6:07

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Vodka is a solution of water and ethanol.

  • Water boils at 100 °C
  • Ethanol boils at 78.37 °C

A mixture of both liquids will start boiling close to the boiling point of ethanol (otherwise distillation wouldn't work).

The lowest boiling temperature is a mixture of:

  • 95.63 mass-% ethanol
  • 4.37 mass-% water

which boils at 78.2 °C.

Read more about this effect at: Azeotrope There is also a picture of a phase diagram there.

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Wait, vodka is quoted at 40% ethanol V/V (so mole fraction about 1/5) and not azeotropic! It should be about 83 °C.

Graph of vapour-liquid equilibrium for mixture of ethanol and water

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  • $\begingroup$ Well, typical vodka has 40%, but one could find even 70% vodka ;) and tobias47n9e didn't claim that it's azeotropic. $\endgroup$
    – Mithoron
    Apr 24, 2015 at 13:07

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