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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 :)