## How to Calculate the Percent Yield of a compound as a result of a reaction:

__Everyday Examples:__- You're back at it again with your sushi restaurant! Now you have 1 order (6 pieces each) of eel avocado rolls to fill. You bought the correct amount of eel and avocado, 12 slices of eel and 6 slices of avocado, but you drop a slice of eel on the floor. Now, you don't have enough eel to fulfill the order. You can only make 5/6 rolls. Therefore, your percent yield is 83%.
- You catch 12 salmon and 12 tuna. The sushi restaurant needs to make 24 salmon tuna rolls. Each salmon yields enough for 2 rolls, and each tuna yields enough for 1 roll. The sushi restaurant will only be able to make 12/24 of the sushi rolls it needs. You sell all of your fish, but the sushi restaurant's percent yield is 50%.

__Equation:__

__% Yield = ( Actual yield / theoretical yield ) x 100__In this type of problem, the phrase “produces” denotes the actual yield and all you have to do is calculate the theoretical yield and plug in the numbers to achieve the percent yield. Also, the limiting reagent in these questions is the reactant that the question mentions. It is just like Using Limiting Reagents, but with an extra step at the end.

There are two types of problems for percent yield. One question gives you the actual yield and asks for the percent yield, and the other gives you the percent yield and asks for the actual yield:

__2 Worked Example Problems:__For the balanced equation shown below, if the reaction of 33.5 grams of H2O produces 53.9 grams of O2, what is the percent yield?

3CO2+4H2O=>C3H8+5O2

**Step 1:**

To answer this question, you use the mass ratio from the balanced equation to determine the theoretical yield.

**Step 2:**

theoretical yield of O2:

(mass of O2)/(mass of H2O)*given mass

160 grams per mole / 72.08 grams per mole * 33.5 grams = 74.4%

**Step 3:**

Then, take the percentage you just found:

(actual/theory)*100=%yield

(53.9/74.4)*100=72.4%

For the balanced equation shown below, if the reaction of 24.2 grams of C6H6O2 produces a 31.9% yield, how many grams of H2O would be produced ?

2C6H6O2+13O2=>12CO2+6H2O

**Step 1:**

To answer this question, you use the mass ratio from the balanced equation to determine the theoretical yield.

**Step 2:**

theoretical yield of H2O:

(mass of H2O)/(mass of C6H6O2)*given mass

(108.12) / (220.2)*24.2 = 11.9

**Step 3:**

Multiplying the theoretical yield by the percent (and dividing by 100), provides the actual yield.

(theory* % yield )/ 100 = actual yield

(11.9*31.9)/100 = 3.80 grams

Ready to move onto the quiz?