Answer:
The mass percentage yield is 85%
Explanation:
<u>Step 1: </u>The balanced equation
2 C7H6O3 + (CH3CO)2CO → 2 C9H8O4 + H20
<u>Step 2</u>: Given data
mass of salicylic acid = 1.03 grams
Volume of acetic anhydride = 2.00 mL = 2*10^-3 L
The product is 1.16 g aspirin synthesized
Molar mass of salicylic acid = 138.12 g/mole
Molar mass of aspirin = 180.16 g/mole
Density of acetic anhydride = 1.0820 g/mL
<u>Step 3</u>: Calculated moles of salicylic acid
Number of moles of salicylic acid = mass of salicylic acid / Molar mass of salicylic acid
Number of moles of salicylic acid = 1.03 grams / 138.12 g/mole
Number of moles of salicylic acid =0.0075 moles
Step 4: Calculated mass acetic anhydride
mass of acetic anhydride = 1.0820 g/mL * 2 mL = 2.164 grams
Step 5: Calculate number of moles of acetic anhydride
Number of moles = 2.164 grams / 102.09 g/moles
Number of moles = 0.0212 moles
<u>Step 6</u>: Find amount of reacting moles
C7H6O3 is the limiting reactant, there will react 0.0075 moles
Since for 2 moles C7H6O3 consumed, we need 1 mole of (CH3CO)2CO to produce 2 moles of C9H804
So for 0.0075 moles C7H6O3 consumed, we produce 0.0075 moles of C9H8O4
<u>Step 7</u>: Calculate mass of aspirin
mass of aspirin = 0.0075 moles * 180 g/mole = 1.35 grams
<u>Step 8:</u> Calculate the mass percentage yield
(1.16 grams / 1.35 grams) * 100% = 85 %
The mass percentage yield is 85%
