Question

A system comprised of chloroform, 1,4-dioxane, and ethanol exists as a two-phase vapor/liquid system at 50∘C and 55 kPa. How many phase-rule variables in addition to T and P must be chosen so as to fix the compositions of both phases? a. 4 b. 2 c. 1 d. 3

Answer 1

The number of phase-rule variables in addition to T and P that must be chosen so as to fix the compositions of both phases is 3.

The correct answer is option (d) 3.

The two-phase vapor/liquid system is a heterogeneous system. Therefore, we should apply the phase rule. The phase rule states that For a heterogeneous system,