# Model/Equations needed to estimate the amount of alcohol and water that would evaporate out of an open glass of bourbon left out uncovered overnight?

Assuming that the bourbon is 45% ethanol, how much water and alcohol would evaporate from an 75 mL glass of whisky left out over uncovered night (I'll say the surface area of liquid exposed to the air initially was 50cm^2 and the distance from the opening of the glass to the liquid surface is 50cm)

I've been able to find Raoult's Law (total vapor pressure is the sum of the vapor pressures of the constituents, multiplied by their mole fraction) and Langmuir's Vapor Equation (a differential equation for the vapor flux over time related to the vapor pressure of the liquid and the partial pressure of the vapor in the gas), but I have no idea how to apply them appropriately, and I'm sure there are people on here that could do much more accurate work than my feeble googling can possibly produce.

• In general this will depend on the shape of the container (which will affect how easy it is to dissipate the layer of vapour that will form above the liquid). That means that you're in for some tough modelling, or that you'll need to include empirical parameters to account for this. – Emilio Pisanty Nov 6 '16 at 11:48
• Not only alcohol (ethanol) will evaporate: see ethanol/water LVE: ddbst.com/en/EED/VLE/VLE%20Ethanol%3BWater.php – Gert Nov 6 '16 at 16:44