STOICHIOMETRY - what is the PERCENTAGE YIELD OF ASPIRIN?

Question

Density of Acetic Acid = 1.082 g/ml

Mass of Salicylic Acid = 5.102 g

Volume of Acetic anhydride = 10.00 ml

Mass of filter paper = 0.0654 g

Mass of watch glass = 8.677 g

Mass of filter paper, watchglass & ASA = 15.062 g

Mass of ASA]= ????

What is the percentage yield of aspirin (ASA)??

Answer 1

you can think of the mass of the aspirin obtained during the experiment as being the actual yield. on this one that would be

15.062 g - 0.0654 g - 8.677 g = 6.32 grams of aspirin

to find the percentage yield then you want to use the underlying formula

percentage yield = (actual yield / theoretical yield) x 100%

for the theoretical yield here then we have

theoretical yield = moles of limiting reactant x molar mass of aspiring

=0.0369 mol x 180.15 g/mol = 6.65 g

meaning that the percentage yield for this scenario is

(6.32 g / 6.65 g) x 100% = 94.97%

Answer 2

Mass of ASA = 15.062g - 8.677g - 0.0654g = 6.3196g