- #1

JameB

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## Homework Statement

Solubility of acetanilide in water is

5.5g/100mL at 100C

0.53g/100mL at 0C

A 0.150g sample of acetanilide containing only traces of impurities was recrystalized using a total of 3mL of hot water.

a) What is the maximum possible percent recovery of pure acetanilide? Show all steps...

b) By how much would the % recovery be reduced if, during vacuum filtration, the crystals were washed with a total of 20mL of ice cold water?

## Homework Equations

Percent recovery equation and basic mathematical operations...

## The Attempt at a Solution

for a) :=

mass that was recrystallized is 0.150g (is this correct assumption?)

maximum acetanilide that could dissolve in water at 100C is 0.165g (100mL = 5.5g then how much is 3mL...)

which implies that max recovery is (0.15/0.165)*100% = 90.9%

Is this right??!

for b) :=

amount that could dissolve in 20mL cold water= 20*0.53/100 = 0.106g

which implies that amount recovered = 0.150-0.106g = 0.044g

which implies that percent recovery is 0.044/0.165*100 = 26.7%

which means that % recovery will be reduced by 64.2%

Am I correct? Thanks :)