Answer:
1.- Theoretical yield is 1.64 g of aspirin
2.- %Yield is 75.6%
Explanation:
The theoretical yield of aspirin could be calculated by the molar relation between anhydride acetic and salicylic acid which is 1:1. It means that the reaction of one mole of anhydride acetic with one mole of salicylic acid will produce 1 mole of aspirin and one mole of acetic acid.
It is possible to calculated the number of moles using moles=grams/molar mass. in the attached figure we can see the molar mass of each compound.
The number of moles of anhydride acetic can be calculated using the density and the volumen.
g=(1.08 g/mL)*(2.90 mL)=3.13 g of anhydride
<em>moles= 3.13 g/(102.09 g/mol)= 0.031 moles of anhydride acetic
</em>
The same for salicylic acid and we have:
<em>moles= 1.23g/ (138.12 g/mol)= 0.0090 moles of salicylic acid
</em>
There is not 1:1 relation between this two compounds because there is much more anhydride acetic than salicylic acid, so the reaction is limited by the 0.0090 moles of salicylic acid which produce 0.0090 moles of aspirin.
g= moles*molar mass
<em>Theoretical yield of aspirin= (0.009 moles)*(182.13 g/mol)= 1.64 g
</em>
The percent yield of aspirin for the reaction can be calculated using the nex formula:
%yield= ((real yield)/(theoretical yield))*100
The real yield was 1.24 g of aspirin
<u><em>%Yield=(1.24g/1.64)*100=75.6%
</em></u>