The solubility of compound A in ethanol is 0.4 g per 100 mL at 0C and 5.0 g per 100 mL at 78C. What is the minimum amount of solvent needed to recrystallize an 8.0 g sample of compound A? How much would be lost in the recrystallization? Show your work.

2 answers

The minimum amount will be the amount ethanol needed to dissolve 8.0 g at 100 C.
That will be 100 mL x (8/5) = 160 mL ethanol needed.

How much is lost.
0.4g x (160/100) = solubility of A in 160 mL ethanol at zero C.
159.36