Final answer:
To calculate percent recovery of a compound such as acetaminophen or aspirin, divide the pure compound obtained post-purification by the initial amount and multiply by 100. Percent composition requires calculating the molar mass of each element in the formula and the total molar mass of the compound.
Step-by-step explanation:
To calculate the percent recovery of acetaminophen and aspirin in a substance, you would first need to know the initial amount of each compound before purification and the amount obtained after purification. Percent recovery is calculated by dividing the weight of the pure compound obtained by the weight of the compound before purification, then multiplying by 100 to obtain a percentage.
For example, if you had 100 mg of a mixture believed to contain acetaminophen and aspirin and after purification, you recovered 90 mg of acetaminophen, the percent recovery for acetaminophen would be (90 mg / 100 mg) * 100, which equals 90%.
Calculating Percent Composition of Aspirin
For aspirin (C9H8O4)'s percent composition, you would calculate the total molar mass of aspirin and then find the percent composition of each element within the molecule. If 81 mg of aspirin is in a 325 mg tablet, the percent of aspirin is (81 mg / 325 mg) * 100, equating to a percentage of 24.92%.