Answer to Question #169539 in Physical Chemistry for khushi

Question

What is the critical solution temperature? Draw and explain the variation of mutual solubility of two liquids which exhibit upper CST.

Answer 1

Critical solution temperature is the maximum temperature at which the two phase region exists

variation of mutual solubility of water and phenol which exhibit upper CST

At respective temperature, like 325 K, point A displays water-rich layer's composition

layer as point A1 shows the composition of phenol-rich layer in equilibrium with A. 

Between these compositions, every mixture will yield 2 layers of compositions A and Al. 

Outside these compositions, the two liquids are soluble mutually at 325 K. Similar behaviour 

is seen at other temperatures below 338.8 K