In Practice Problem 12.3, you learned that “proof” for an alcoholic drink equals twice the percentage of alcohol in the drink. The complete definition of proof is that it is twice the percentage by volume of alcohol. Knowing this, exactly what does it mean to have a 90-proof drink?

Data from Problem 12.3

The “proof” value of any liquor is equal to twice the percentage of alcohol; for example, a 50-proof liquor is 25% alcohol in water. Vodka is normally sold between 80 and 100 proof, but suppose you came across a bottle of 135-proof vodka. Would you be justified in calling the alcohol the solvent and the water the solute? Explain.