1. Liquid-Liquid Phase Equilibrium
Experiment will be performed in hood

2. Purpose
To study the miscibility of a binary liquid system as a function of temperature and composition.
To determine the distribution coefficient of a binary liquid system.
To construct a phase diagram.
To determine the critical temperature and mole fraction for the binary system.

3. Distribution Coefficient
When methanol and cyclohexane are mixed, there is partial miscibility and two liquid phases are observed. Each phase contains both components.
The distribution coefficient is a quantitative measure of how methanol distributes itself quantitatively in each phase. Similarly for cyclohexane.

4. Critical T and x Miscibility changes with T and x, mole fraction.
When T is changed for a binary system of constant composition, we can observe the transition from 1-phase to 2-phases and record the transition T.
When this T is plotted vs x, the curve may have a maximum or minimum. This is called the critical point.

5. Experimental Procedure
Construct a T vs x phase diagram and find the critical point for the methanol-cyclohexane system.
Determine the distribution coefficient of the methanol-cyclohexane system.