1.The solubility of benzoic acid in water is 6.80 g per 100 mL at 100 °C and 0.34 g per 100 mL at 25 °C.
a) Calculate the minimum volume of water needed to dissolve 1.00 g of benzoic acid at 100 °C.
b) Calculate the maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water, assuming the solution is filtered at 25 °C.
2. The solubility of acetanilide in your recrystallizing solvent is 5.0 mg per mL at 10 °C.
a)Calculate the maximum percent recovery in this experiment, assuming a 15.0-mL recrystallizing solution is filtered at 10 °C.
b) Calculate the percentage recovery of acetanilide produced in your experiment.
c)How do your results compare to the maximum percent recovery? Briefly explain.
3. A student rushed through this experiment. Describe the effect that the following procedural changes would have on the percent recovery of acetanilide. Briefly explain the basis of each answer.
a) Rather than adding 0.5-mL portions of boiling solvent to the acetanilide, the student added 5-mL portions of boiling solvent.
b) The student did not pre-heat the gravity filtration apparatus in Part 3.
c) The student forgot to cool 5 mL of solvent in Part 5 and washed the crystals with room temperature solvent.