2. Determine the theoretical yield of aspirin if you started with 2.500 grams of salicylic acid?
To determine the theoretical yield of aspirin, we need to know the balanced chemical equation for the synthesis reaction of aspirin from salicylic acid.
The balanced chemical equation for the synthesis of aspirin from salicylic acid is as follows:
C₇H₆O₃ (salicylic acid) + C₄H₆O₃ (acetic anhydride) → C₉H₈O₄ (aspirin) + CH₃COOH (acetic acid)
From the equation, we can see that one mole of salicylic acid reacts with one mole of acetic anhydride to produce one mole of aspirin.
To calculate the theoretical yield of aspirin, we need to convert the mass of salicylic acid to moles using the molar mass.
The molar mass of salicylic acid (C₇H₆O₃) is:
(7 x Atomic mass of Carbon) + (6 x Atomic mass of Hydrogen) + (3 x Atomic mass of Oxygen)
= (7 x 12.01 g/mol) + (6 x 1.01 g/mol) + (3 x 16.00 g/mol)
= 138.12 g/mol
Using the molar mass of salicylic acid, we can calculate the number of moles of salicylic acid:
Number of moles = Mass / Molar mass
Number of moles = 2.500 g / 138.12 g/mol
Number of moles ≈ 0.0181 mol
Since the balanced equation tells us that one mole of salicylic acid produces one mole of aspirin, the theoretical yield of aspirin is also 0.0181 moles.
Finally, to convert moles of aspirin to grams, we use the molar mass of aspirin.
The molar mass of aspirin (C₉H₈O₄) is:
(9 x Atomic mass of Carbon) + (8 x Atomic mass of Hydrogen) + (4 x Atomic mass of Oxygen)
= (9 x 12.01 g/mol) + (8 x 1.01 g/mol) + (4 x 16.00 g/mol)
= 180.16 g/mol
The theoretical yield of aspirin in grams can be calculated as:
Theoretical yield = Number of moles x Molar mass
Theoretical yield = 0.0181 mol x 180.16 g/mol
Theoretical yield ≈ 3.27 grams
Therefore, the theoretical yield of aspirin, starting with 2.500 grams of salicylic acid, is approximately 3.27 grams.
To determine the theoretical yield of aspirin, you need to know the balanced chemical equation for the reaction between salicylic acid and acetic anhydride to form aspirin. The balanced equation is:
C7H6O3 + C4H6O3 → C9H8O4 + C2H4O2
From the equation, we can see that one mole of salicylic acid (C7H6O3) reacts with one mole of acetic anhydride (C4H6O3) to yield one mole of aspirin (C9H8O4) and one mole of acetic acid (C2H4O2).
To determine the theoretical yield, we need to convert the mass of salicylic acid to moles using its molar mass, then use the mole ratio from the balanced equation to calculate the theoretical yield of aspirin.
1. Calculate the molar mass of salicylic acid (C7H6O3):
The atomic masses for carbon (C), hydrogen (H), and oxygen (O) are 12.01 g/mol, 1.01 g/mol, and 16.00 g/mol, respectively.
Molar mass of salicylic acid = (7 * molar mass of C) + (6 * molar mass of H) + (3 * molar mass of O)
= (7 * 12.01 g/mol) + (6 * 1.01 g/mol) + (3 * 16.00 g/mol)
= 138.12 g/mol
2. Convert the mass of salicylic acid to moles:
Moles of salicylic acid = mass of salicylic acid / molar mass of salicylic acid
= 2.500 g / 138.12 g/mol
3. Use the mole ratio from the balanced equation to calculate the moles of aspirin:
From the balanced equation, the mole ratio between salicylic acid and aspirin is 1:1.
Moles of aspirin = Moles of salicylic acid
4. Calculate the theoretical yield of aspirin in grams:
The molar mass of aspirin (C9H8O4) can be calculated in a similar manner as done for salicylic acid:
Molar mass of aspirin = (9 * molar mass of C) + (8 * molar mass of H) + (4 * molar mass of O)
= (9 * 12.01 g/mol) + (8 * 1.01 g/mol) + (4 * 16.00 g/mol)
= 180.16 g/mol
Theoretical yield of aspirin = Moles of aspirin * molar mass of aspirin
Now, substitute the values into the equation to calculate the theoretical yield.