Question

Aspirin balanced reaction is 1 salicylic acid (138g/mol) + 1 acetic anhydride (102g/mol) -> 1 aspirin (180g/mol). If you are able to convert 50 g of salicylic acid into 40 g of aspirin what is the yield for this reaction?

a 56.6%

b 61.3%

c 80.0%

d 92.3%

Answer 1

Step 1: Explanation:

A mole ratio is ​the ratio between the amounts in moles of any two compounds involved in a chemical reaction. The mole ratio can be determined by examining the coefficients in front of formulas in a balanced chemical equation.

Step 2: write the balanced chemical equation.

C₇H₆O₃ + C₄H₆O₃ ------> C₉H₈O₄ + C₂H₄O₂

Step 3: calculate the moles of salicylic acid

we know, moles = mass given / molar mass

moles of salicylic acid (C₇H₆O₃ ) = ( 50 g / 138 g/mol ) = 0.362319 mol

Step 4: Calculate the mass of  Aspirin produced

C₄H₆O₃ + C₇H₆O₃---> C₉H₈O₄ + C₂H₄O₂

According to the reaction:
1 mol of Salicylic acid produce 1 mol of Aspirin
so, 0.362319 mol of Salicylic acid will produce = 0.362319 mol of Aspirin

hence, mass of Aspirin produced = ( moles × molar mass ) = (0.362319 mol ×180 g/mol ) = 65.22 g

step 5: Calculation of percent yield of Aspirin

Given, actual yield = 40 g

We got theoretical yield = 65.22 g

We know, Percent yield = (actual yield / theoretical yield ) × 100 %

Percent yield = (40 g / 65.22 ) × 100 % = 61.3 %

Hence, the percent yield of reaction = 61.3 % --------> option(b)