Chapter 9, Problem 43A

Interpretation Introduction

Interpretation:The reasons of lesser actual yield than theoretical yield that makes the percent yield lesser than 100% for a chemical reaction needs to be explained.

Concept Introduction: A chemical reaction involves the conversion of reactant to product by breaking and making of chemical bonds.

There can be more than one reactant molecules involve in a chemical reaction to form the products. The reactant which is present in limited amount in a chemical reaction is called as limiting reactant.

Answer to Problem 43A

• Reactions in solution may dissolve some of the product due to its solubility.
• For a reversible reaction, the equilibrium may reach before complete conversion of reactant molecules can decrease the actual yield.
• The more solubility can reduce the mass of product during filtration also as some of the solid product remains on filter paper also.

Explanation of Solution

The actual yield of the product is the amount of product which is formed at the end of reaction experimentally, whereas theoretical yield represents the amount of product calculated by expecting that 100 % of reactant changes to product. The percent yield can be shown as:

  $\text{Percent yield = }\frac{\text{Actual yield}}{\text{Theoretical yield}}\text{ x 100}$

Due to different experimental errors, the actual yield is always lesser than theoretical yield. Some other reasons are as listed below:

• Reactions in solution may dissolve some of the product due to its solubility.
• For a reversible reaction, the equilibrium may reach before complete conversion of reactant molecules can decrease the actual yield.
• The more solubility can reduce the mass of product during filtration also as some of the solid product remains on filter paper also.

Conclusion

Due to experimental errors, the actual yield is lesser than theoretical yield.