If 1.87 g of acetic acid(CH3CO2H) reacts with 2.31 g of isopentyl alcohol(C5H12O) to give 2.96 g of isopentyl acetate(C7H14O2), what is the percent yield of the reaction?
To find the percent yield of a reaction, you need to compare the actual yield (the amount of product obtained in the experiment) to the theoretical yield (the amount of product that should theoretically be obtained based on stoichiometry).
First, calculate the molecular weights of the compounds involved:
- Acetic acid (CH3CO2H): Molar mass = 2(1.01) + 4(1.01) + 16.00 + 1.01 = 60.05 g/mol
- Isopentyl alcohol (C5H12O): Molar mass = 5(12.01) + 12(1.01) + 16.00 = 88.15 g/mol
- Isopentyl acetate (C7H14O2): Molar mass = 7(12.01) + 14(1.01) + 2(16.00) = 130.19 g/mol
Next, determine the limiting reagent by calculating the number of moles for each reactant:
- Acetic acid: moles = mass / molar mass = 1.87 g / 60.05 g/mol ≈ 0.0311 mol
- Isopentyl alcohol: moles = mass / molar mass = 2.31 g / 88.15 g/mol ≈ 0.0262 mol
Based on the stoichiometry of the balanced equation, the reaction ratio between acetic acid and isopentyl alcohol is 1:1. Therefore, isopentyl alcohol is the limiting reagent as it is in a lower quantity.
Now, calculate the theoretical yield of isopentyl acetate using the stoichiometry:
- From the balanced equation, we know that 1 mol of isopentyl alcohol produces 1 mol of isopentyl acetate.
- Therefore, the number of moles of isopentyl acetate formed is also approximately 0.0262 mol.
Convert the moles of isopentyl acetate to mass:
- mass = moles * molar mass = 0.0262 mol * 130.19 g/mol ≈ 3.41 g
Finally, calculate the percent yield:
- Percent yield = (actual yield / theoretical yield) * 100
- Percent yield = (2.96 g / 3.41 g) * 100 ≈ 86.8%
Therefore, the percent yield of the reaction is approximately 86.8%.