Percent yield is a topic of chemistry that is widely used in the experiments of chemical reactions. Percent yield is one of the forms of yield. Yield is a measure of the number of moles of a product created in a chemical reaction with the amount of reactant consumed, usually represented as a percentage. The difference between the actual amount of product produced and the maximum calculated yield is the percentage yield.

In this post, we will cover the basics of percent yield along with a lot of examples.

What is Percent Yield?

In chemistry, the weight of the product obtained divided by the theoretical yield is known as percent yield. To represent the final answer in percent, divide the experimental yield by the theoretical yield and multiply the result by 100. Because the actual yield attained after the reaction is generally less than the theoretical value, the percent yield is usually less than 100 percent. This may be due to an incomplete reaction.

Percent yield can also be higher than 100%, indicating that more sample was recovered from the reaction than was projected initially. The yield on investment is usually positive.

In simple words, the actual yield divided by the theoretical yield is said to be the present yield.

The theoretical yield is the amount of product you can expect to acquire following a reaction. It’s the expected amount of product after the entire limiting reactant has been utilized. While the actual yield is the total number of products generated when the reaction has been completed. It’s the final product you’re holding after the experiment. You can also calculates it with best electrical engineering calculator. These calculators are programable and fully scientific.

To better comprehend the idea of percent yield, consider the breakdown reaction of magnesium oxide.

MgCO3 → MgO + CO2

This means that we will get 1 mole of product [MgO] for 1 mole of reactant [MgCO3] i.e., the reactant and product have a 1:1 mole ratio. By comparing the mole ratio with the amount of reactant, we may find the theoretical yield.

Percent yield = % yield = (actual yield/ theoretical yield) x 100%

How to calculate percent yield?

By using the following formula, we can easily solve the percent yield in the experiment.

Percent yield = % yield = (actual yield/ theoretical yield) x 100%

Example 1

In a chemical reaction of an experiment, the actual yield is 35g and the theoretical yield is 34g, compute the percent yield.

Solution

Step 1: Identify the values.

Theoretical yield = 34g

Actual yield = 35g

Step 2: Write the general formula.

Percent yield = % yield = (actual yield/ theoretical yield) x 100%

Step 3: Put the values in the above formula.

Percent yield = (35/34) x 100%

Percent yield = 1.029 x 100% = 102.9%

Thus, the percent yield in the given experiment is 102.9%.

Example 2

In a chemical reaction of an experiment, the actual yield is 5g and the theoretical yield is 6.34g, compute the percent yield.

Solution

Step 1: Identify the values.

Theoretical yield = 6.34g

Actual yield = 5g

Step 2: Write the general formula.

Percent yield = % yield = (actual yield/ theoretical yield) x 100%

Step 3: Put the values in the above formula.

Percent yield = (5/6.34) x 100%

Percent yield = 0.789 x 100% = 78.9%

Thus, the percent yield in the given experiment is 78.9%.

How to calculate the actual yield and theoretical yield if the percent yield is given?

By modifying the formula of percent yield, we can also calculate the actual yield and theoretical yield if the percent yield is given. We can calculate accurate results of the percent yield, actual yield, and theoretical yield by using the percent yield calculator.

Theoretical yield = (actual yield/ percent yield) x 100%

Actual yield = % yield x theoretical yield / 100

Examples to evaluate the theoretical yield.

Example 1

If the percent yield in the experiment is 105% and the chemical reaction has an actual yield of 15g, calculate the theoretical yield of the chemical reaction.

Solution:

Step 1: Identify the values.

Percent yield = 105%

Actual yield = 15g

Step 2: Write the general formula.

Theoretical yield = (actual yield/ percent yield) x 100

Step 3: Put the values in the above formula.

Theoretical yield = (15/105) x 100

Theoretical yield = 0.1429 x 100 = 14.29g

Thus, the Theoretical yield in the given experiment is 14.29g.

Example 2

If the percent yield in the experiment is 65% and the chemical reaction has an actual yield of 45g, calculate the theoretical yield of the chemical reaction.

Solution

Step 1: Identify the values.

Percent yield = 65%

Actual yield = 45g

Step 2: Write the general formula.

Theoretical yield = (actual yield/ percent yield) x 100

Step 3: Put the values in the above formula.

Theoretical yield = (45/65) x 100

Theoretical yield = 0.6923 x 100 = 69.23g

Thus, the Theoretical yield in the given experiment is 69.23g.

Examples to evaluate the actual yield.

Example 1

If the percent yield in the experiment is 115% and the chemical reaction has a theoretical yield of 35g, calculate the actual yield of the chemical reaction.

Solution

Step 1: Identify the values.

Percent yield = 115%

Theoretical yield = 35g

Step 2: Write the general formula.

Actual yield = % yield x theoretical yield / 100

Step 3: Put the values in the above formula.

Actual yield = 115 x 35 / 100

Actual yield = 4025 / 100 = 40.25g

Thus, the actual yield in the given experiment is 40.25g.

Example 2

If the percent yield in the experiment is 15% and the chemical reaction has a theoretical yield of 5g, calculate the actual yield of the chemical reaction.

Solution

Step 1: Identify the values.

Percent yield = 15%

Theoretical yield = 50g

Step 2: Write the general formula.

Actual yield = %  yield x theoretical yield / 100

Step 3: Put the values in the above formula.

Actual yield = 15 x 50 / 100

Actual yield = 750 / 100 = 75.0g

Thus, the actual yield in the given experiment is 75.0g.

Summary

Percent yield is obtained by calculating the results of the division of actual yield and the theoretical yield. We use a formula to find the value of the percent yield. Percent yield is either less than 100% or greater. We can also calculate the actual yield and theoretical yield if the percent yield is given.

 

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