Introduction
Aspirin, also known as acetylsalicylic acid, is a common pain reliever and anti-inflammatory medication. It is synthesized from salicylic acid, which is found in the bark of willow trees and other plants. In this article, we will discuss the number of moles of aspirin that can be produced from a given amount of salicylic acid.
Theoretical Yield
The theoretical yield is the maximum amount of product that can be produced from a given amount of reactants. In the case of synthesizing aspirin from salicylic acid, the theoretical yield can be calculated using the balanced chemical equation: C7H6O3 + C4H6O3 → C9H8O4 + C2H4O2 This equation shows that one mole of salicylic acid (C7H6O3) reacts with one mole of acetic anhydride (C4H6O3) to produce one mole of aspirin (C9H8O4) and one mole of acetic acid (C2H4O2).
Actual Yield
The actual yield is the amount of product that is obtained from a chemical reaction in practice. The actual yield is often less than the theoretical yield due to factors such as incomplete reaction or loss of product during filtration or purification.
Calculating Moles of Aspirin
To calculate the number of moles of aspirin produced from a given amount of salicylic acid, we must first determine the amount of salicylic acid used in the reaction and the actual yield of aspirin. For example, if we start with 5 grams of salicylic acid and obtain 4 grams of aspirin as the actual yield, we can calculate the number of moles of aspirin as follows: 1. Convert the mass of salicylic acid to moles by dividing by its molar mass (138.12 g/mol): 5 g / 138.12 g/mol = 0.0362 mol 2. Use the balanced chemical equation to determine the number of moles of aspirin produced based on the number of moles of salicylic acid used: 0.0362 mol salicylic acid × 1 mol aspirin / 1 mol salicylic acid = 0.0362 mol aspirin 3. Compare the actual yield to the theoretical yield to calculate the percent yield: Actual yield / Theoretical yield × 100% = Percent yield In this example, the theoretical yield can be calculated using the stoichiometry of the balanced chemical equation: 1 mol salicylic acid produces 1 mol aspirin 5 g salicylic acid × 1 mol / 138.12 g = 0.0362 mol salicylic acid 0.0362 mol salicylic acid × 1 mol aspirin / 1 mol salicylic acid = 0.0362 mol aspirin The theoretical yield is 0.0362 mol aspirin. The percent yield can be calculated as: 4 g / (0.0362 mol × 180.16 g/mol) × 100% = 70.9%
Conclusion
In conclusion, the number of moles of aspirin produced from salicylic acid can be calculated using the balanced chemical equation and the actual yield of the reaction. The theoretical yield represents the maximum possible amount of product that can be obtained, while the actual yield is the amount that is obtained in practice. The percent yield is a measure of the efficiency of the reaction and can be calculated by comparing the actual yield to the theoretical yield.