1.15g of acetylsalicylic ia recovered from an aspirim synthesis reaction that began with 2g of salicylic acid, what would be the percentage yield for the preparation? show your computations
Salicylic Acid + Acetic Anhydride.......=>..........Aspirin + Acetic Acid
…..C₇H₆O₃…….. + …..C₄H₆O₃……… =>……...C₉H₈O₄ + HC₂H₃O₂
2g/(138g/mol)….+.....(excess)………=> ?g(Theoretical) + ----------
=0.015mole C₇H₆O₃..…………………=>…0.015mole(180g/mole) = 2.61g Aspirin (Theoretical Yield)
%Yield = (Actual Yield/Theoretical Yield)100% = (1.15g/2.61g)100% = 44.1% Yield
To calculate the percentage yield for the preparation, first, we need to determine the theoretical yield.
Step 1: Calculate the molar mass of salicylic acid (C7H6O3)
Molar mass of C = 12.01 g/mol
Molar mass of H = 1.01 g/mol
Molar mass of O = 16.00 g/mol
Molar mass of salicylic acid (C7H6O3) = (7*12.01) + (6*1.01) + (3*16.00) = 138.12 g/mol
Step 2: Calculate the number of moles of salicylic acid
Number of moles = mass / molar mass
Number of moles of salicylic acid = 2 g / 138.12 g/mol
Step 3: Convert the number of moles of salicylic acid to the number of moles of acetylsalicylic acid (aspirin)
Since acetylsalicylic acid and salicylic acid have a 1:1 stoichiometric ratio, the number of moles of acetylsalicylic acid will be the same as that of salicylic acid.
Step 4: Calculate the mass of acetylsalicylic acid (aspirin) using the number of moles obtained in the previous step
Mass = number of moles * molar mass
Mass of acetylsalicylic acid = 2 g / 138.12 g/mol * 138.12 g/mol
Step 5: Calculate the percentage yield
Percentage yield = (actual yield / theoretical yield) * 100
= (1.15 g / Mass of acetylsalicylic acid) * 100
Now, let's calculate the percentage yield:
Mass of acetylsalicylic acid = 2 g / 138.12 g/mol * 138.12 g/mol
= 2 g
Percentage yield = (1.15 g / 2 g) * 100
= 57.5%
Therefore, the percentage yield for the preparation is 57.5%.
To calculate the percentage yield for the preparation of acetylsalicylic acid, we first need to determine the theoretical yield and the actual yield.
The theoretical yield is the maximum amount of acetylsalicylic acid that could be obtained from the given amount of salicylic acid. In this case, we will assume that the reaction goes to completion and all of the salicylic acid is converted to acetylsalicylic acid.
The molar masses are:
Salicylic acid = 138.12 g/mol
Acetylsalicylic acid = 180.16 g/mol
Step 1: Convert the mass of salicylic acid to moles.
2 g salicylic acid * (1 mol salicylic acid / 138.12 g salicylic acid) = 0.01448 mol salicylic acid
Step 2: Convert the moles of salicylic acid to moles of acetylsalicylic acid. Since the reaction is assumed to be stoichiometric, the mole ratio is 1:1.
0.01448 mol salicylic acid * (1 mol acetylsalicylic acid / 1 mol salicylic acid) = 0.01448 mol acetylsalicylic acid
Step 3: Convert the moles of acetylsalicylic acid to grams.
0.01448 mol acetylsalicylic acid * 180.16 g acetylsalicylic acid / 1 mol acetylsalicylic acid = 2.61 g acetylsalicylic acid (theoretical yield)
Now, we can calculate the percentage yield using the actual yield.
Actual yield = 1.15 g acetylsalicylic acid
Percentage yield = (Actual yield / Theoretical yield) * 100
= (1.15 g / 2.61 g) * 100
= 44.06%
Therefore, the percentage yield for the preparation is 44.06%.