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Phase changes of phenol chloroform - (Dec/01/2012 )

When you mix phenol and chloforom together, shake, and let sit, 2 apparent phases form. Then when you add an aqueous solution, shake up, and let sit, you still only get 2 apparent phases. Why don't you get 3 phases?


The "phenol" you are mixing is liquid, and is really a solution of phenol in water. Mixing with chloroform moves much of the phenol into the chloroform phase, but leaves water behind. When you add an aqueous solution, it mixes primarily with the water already present. Pure phenol (solid) will dissolve in chloroform with no second phase.