Theoretical Yield Calculator

Theoretical Yield Definition

 It is the amount of product obtained when the whole of the limiting reactant used in a reaction is completely converted into the products without any loss of reactants. It is the product of a perfect chemical reaction.

Limiting reactant decides the amount of product obtained. It helps in increasing the yield of a reaction. The excess reactant is the reactant of which some quantity is left by the end of the reaction.

Theoretical yield formula

Most of the time we are asked to find the theoretical yield from actual and percentage yield. The theoretical yield equation is:

$\text{Theoretical yield =}$ $\dfrac{\text{Autual yield}}{\text{Percentage yield}} \times 100$

Actual yield is the amount of product obtained when the reaction is actually performed. Percentage yield is the ratio of actual yield to the theoretical yield multiplied by 100. It is 100 percent for a reaction whose actual and theoretical yield is the same.

How to calculate the theoretical yield?

Example:

An experiment is carried out in a laboratory. The actual yield of the experiments is 10 grams and the percentage yield is 90 percent. Calculate the theoretical yield.

Solution: 

Step 1: Identify the percentage and actual yield.

Actual yield = 10 grams

Percentage yield = 90 percent

Step 2: Write the formula and put the identified values.

$\text{Theoretical yield =}$ $\dfrac{\text{Autual yield}}{\text{Percentage yield}} \times 100$

$\text{Theoretical yield =}$ $\dfrac{\text{10}}{\text{90}} \times 100$

$\text{Theoretical yield = 12.5}$

Why is it called “theoretical” yield?

Theoretical means involving theory. It is the calculated product without performing any experiment. No laboratory reaction is a perfect chemical reaction.

It is not possible to convert all of the reactants completely into the required product without producing any by-products or preventing any side reaction to take place.