In: Chemistry
Aspirin can be prepared from salicylic acid ( C 7 H 6 O 3 ), which has a molar mass of 138.12 g/mol, and acetic anhydride ( C 4 H 6 O 3 C 4 H 6 O 3 ), which has a molar mass of 102.04 g/mol. The density of acetic anhydride is 1.082 g/mL.
C 7 H 6 O 3 + C 4 H 6 O 3 ⟶ C 9 H 8 O 4 + C 2 H 3 O 2
What is the theoretical yield of aspirin ( C 9 H 8 O 4 ), which has a molar mass of 180.15 g/mol, possible when reacting 3.19 g of salicylic acid with 3.75 mL of acetic anhydride?
mass of acetic anhydride = volume * density
= 3.75*1.082 = 4.0575g
no of moles of salicylic acid = W/G.M.Wt
= 3.19/138.12 = 0.023moles
no of moles of acetic anhydride = W/G.M.Wt
= 4.0575/102.04 = 0.039764moles
C 7 H 6 O 3 + C 4 H 6 O 3 ⟶ C 9 H 8 O 4 + C 2 H 3 O 2
1 mole of acetic anhydride react with 1 mole of salicylic acid
0.039764 moles of anhydride react with 0.039764mole of salicylic acid
salicylic acid is limiting reactant
1 mole of salicylic acid react with excess of acetic anhydride to gives1 mole of asprine
0.023 mole of salicylic acid react with excess of acetic anhydride to gives 0.023 mole of asprine
theoretical yield of asprine = no of moles * gram molar mass
= 0.023*180.15 = 4.14345g >>>>answer