Consider The Balanced Equation:${ N_2 + 3 H_2 \rightarrow 2 NH_3 }$What Is The Percent Yield Of { NH_3 $}$ If The Reaction Of 26.3 G Of { H_2 $}$ Produces 79.0 G Of { NH_3 $}$?Use The Formula: $[%

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Understanding Percent Yield

Percent yield is a measure of the efficiency of a chemical reaction. It is the ratio of the actual yield of a product to its theoretical yield, expressed as a percentage. In other words, it is a measure of how much of the product is actually produced compared to how much is expected to be produced based on the balanced equation.

The Balanced Equation

The balanced equation for the reaction between nitrogen and hydrogen to form ammonia is:

N2+3H2→2NH3{ N_2 + 3 H_2 \rightarrow 2 NH_3 }

This equation tells us that 1 mole of nitrogen reacts with 3 moles of hydrogen to produce 2 moles of ammonia.

Calculating Theoretical Yield

To calculate the theoretical yield of ammonia, we need to know the number of moles of hydrogen that reacted. We can calculate this by dividing the mass of hydrogen by its molar mass.

The molar mass of hydrogen is 2.016 g/mol. Therefore, the number of moles of hydrogen is:

moles of H2=mass of H2molar mass of H2=26.3 g2.016 g/mol=13.05 mol{ \text{moles of H}_2 = \frac{\text{mass of H}_2}{\text{molar mass of H}_2} = \frac{26.3 \text{ g}}{2.016 \text{ g/mol}} = 13.05 \text{ mol} }

Since 3 moles of hydrogen are required to produce 2 moles of ammonia, the number of moles of ammonia produced is:

moles of NH3=23×moles of H2=23×13.05 mol=8.7 mol{ \text{moles of NH}_3 = \frac{2}{3} \times \text{moles of H}_2 = \frac{2}{3} \times 13.05 \text{ mol} = 8.7 \text{ mol} }

The molar mass of ammonia is 17.031 g/mol. Therefore, the theoretical yield of ammonia is:

theoretical yield of NH3=moles of NH3×molar mass of NH3=8.7 mol×17.031 g/mol=147.9 g{ \text{theoretical yield of NH}_3 = \text{moles of NH}_3 \times \text{molar mass of NH}_3 = 8.7 \text{ mol} \times 17.031 \text{ g/mol} = 147.9 \text{ g} }

Calculating Percent Yield

The actual yield of ammonia is 79.0 g. To calculate the percent yield, we can use the formula:

percent yield=actual yieldtheoretical yield×100%{ \text{percent yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100\% }

Substituting the values, we get:

percent yield=79.0 g147.9 g×100%=53.5%{ \text{percent yield} = \frac{79.0 \text{ g}}{147.9 \text{ g}} \times 100\% = 53.5\% }

Therefore, the percent yield of ammonia is 53.5%.

Conclusion

Percent yield is an important concept in chemistry that helps us understand the efficiency of a chemical reaction. By calculating the theoretical yield and actual yield of a product, we can determine the percent yield and identify areas for improvement in the reaction.

Importance of Percent Yield

Percent yield is important because it helps us:

  • Evaluate the efficiency of a chemical reaction
  • Identify areas for improvement in the reaction
  • Optimize reaction conditions to increase yield
  • Compare the yield of different reactions

Real-World Applications

Percent yield has many real-world applications, including:

  • Industrial processes: Percent yield is used to evaluate the efficiency of industrial processes, such as the production of chemicals and pharmaceuticals.
  • Quality control: Percent yield is used to ensure that products meet quality standards.
  • Research and development: Percent yield is used to optimize reaction conditions and improve the yield of new products.

Common Mistakes

When calculating percent yield, it is common to make mistakes, such as:

  • Incorrect calculation of theoretical yield
  • Incorrect calculation of actual yield
  • Incorrect use of the formula for percent yield

To avoid these mistakes, it is essential to:

  • Double-check calculations
  • Use the correct formula for percent yield
  • Ensure that all values are in the correct units

Conclusion

Frequently Asked Questions

Q: What is percent yield?

A: Percent yield is a measure of the efficiency of a chemical reaction. It is the ratio of the actual yield of a product to its theoretical yield, expressed as a percentage.

Q: How do I calculate percent yield?

A: To calculate percent yield, you need to know the actual yield and theoretical yield of a product. The formula for percent yield is:

percent yield=actual yieldtheoretical yield×100%{ \text{percent yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100\% }

Q: What is the difference between actual yield and theoretical yield?

A: Actual yield is the amount of product actually produced in a reaction, while theoretical yield is the amount of product that is expected to be produced based on the balanced equation.

Q: Why is percent yield important?

A: Percent yield is important because it helps us evaluate the efficiency of a chemical reaction and identify areas for improvement. It also helps us optimize reaction conditions to increase yield and compare the yield of different reactions.

Q: How do I calculate theoretical yield?

A: To calculate theoretical yield, you need to know the number of moles of reactants that reacted and the molar mass of the product. The formula for theoretical yield is:

theoretical yield=moles of reactants×molar mass of product{ \text{theoretical yield} = \text{moles of reactants} \times \text{molar mass of product} }

Q: What are some common mistakes to avoid when calculating percent yield?

A: Some common mistakes to avoid when calculating percent yield include:

  • Incorrect calculation of theoretical yield
  • Incorrect calculation of actual yield
  • Incorrect use of the formula for percent yield
  • Failure to ensure that all values are in the correct units

Q: How do I optimize reaction conditions to increase yield?

A: To optimize reaction conditions to increase yield, you need to consider factors such as temperature, pressure, and concentration of reactants. You can also try different reaction conditions, such as changing the solvent or adding a catalyst, to see if they improve the yield.

Q: Can I use percent yield to compare the yield of different reactions?

A: Yes, you can use percent yield to compare the yield of different reactions. By calculating the percent yield of each reaction, you can determine which reaction is more efficient and which conditions are most effective.

Q: What are some real-world applications of percent yield?

A: Some real-world applications of percent yield include:

  • Industrial processes: Percent yield is used to evaluate the efficiency of industrial processes, such as the production of chemicals and pharmaceuticals.
  • Quality control: Percent yield is used to ensure that products meet quality standards.
  • Research and development: Percent yield is used to optimize reaction conditions and improve the yield of new products.

Q: How do I use percent yield in my own research or industrial process?

A: To use percent yield in your own research or industrial process, you need to:

  • Calculate the actual yield and theoretical yield of your product
  • Use the formula for percent yield to calculate the percent yield
  • Compare the percent yield to the expected yield to determine the efficiency of your reaction
  • Use the results to optimize reaction conditions and improve the yield of your product.

Conclusion

In conclusion, percent yield is an important concept in chemistry that helps us evaluate the efficiency of a chemical reaction and identify areas for improvement. By calculating the actual yield and theoretical yield of a product, we can determine the percent yield and use it to optimize reaction conditions and improve the yield of our product.