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# How to Calculate Percent Yield in Chemistry

❶Calculate the molar mass of each reactant.

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For this example, use the equation: This percentage tells you the efficiency of the chemical reaction, or how good the reaction is at actually producing the desired product. High percentages such as this one indicate better yields, and low percentages indicate poor yields.

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Ezell; Updated April 24, Here's a Calculator to Help You X. Matter and Change; Laurel Dingrando, et al. How to Calculate Percent Yield. Depending on which text editor you're pasting into, you might have to add the italics to the site name. Convert the result to grams. Multiply your answer in moles by the molar mass of that compound to find the theoretical yield in grams. This is a more convenient unit to use in most experiments. The theoretical yield of the experiment is The theoretical yield you calculated assumes that everything went perfectly.

In an actual experiment, this never happens: This is why chemists use 3 different concepts to refer to yield: The theoretical yield is the maximum amount of product the experiment could make. The actual yield is the actual amount you created, measured directly on a scale.

Write down the actual yield of the experiment. If you performed the experiment yourself, gather the purified product from your reaction and weigh it on a balance to calculate its mass.

If you are working on a homework problem or someone else's notes, the actual yield should be listed. Divide the actual yield by the theoretical yield. Make sure you use the same units for both values typically grams.

Your answer will be a unit-less ratio. The actual yield was 29 grams, while the theoretical yield was Multiply by to convert to a percentage.

The answer is the percent yield. If in the reaction is below 32 of C2H6 and produces 44 grams of CO2, what is the percent yield? This is your theoretical yield based on the 32g of C2H6 you started with and the molar ratio between C2H6 and CO2 in your balanced equation.

Not Helpful 0 Helpful 1. You can determine this by the coefficients in front of your desired reactant and product in your balanced equation. Not Helpful 1 Helpful 1. How do I calculate the percentage yield when I'm only given the volume of the reactants? Not Helpful 6 Helpful Well water is composed of 3 atoms, 2 hydrogen and 1 oxygen.

Not Helpful 7 Helpful What do I do with mols in different atoms when calculating the percentage yield? Actual yield divided by theoretical yield. Not Helpful 10 Helpful How do I calculate the limiting reactant when calculating the percent yield? Find the number of moles of the reactants and compare them.

The reactant with the least number of moles will be your limiting reactant. Actual yield is the mass that will be given to you after the experiment or in the exam question. However, the actual yield will nearly always be given. Not Helpful 7 Helpful 1.

If you get wildly different results, check your units. If your actual yield is different from your theoretical yield by an order of magnitude or more, you probably used the wrong units at some point in your calculations. Repeat the calculations and keep track of your units each step of the way. Purify the product such as by drying or filtering and weigh it again.

By using this service, some information may be shared with YouTube. Quick Summary To calculate a percentage yield in chemistry, start with a balanced chemical equation, with the reactants on the left side and the products on the right.

Cookies make wikiHow better. By continuing to use our site, you agree to our cookie policy. JW Jeff Williams Apr NN Nur Nour Aug 28, I managed to answer my question by just following steps in part 2 and part 3. EB Ed Blackman May 18, I struggle with chemistry, so this simplified and explained the calculations I had failed to do myself.

MS Mehgan Suller Sep 27, KC Katherine Colon Nov 14, Next week I start a course of chemistry. AJ Alyson Jadlocki Jan 31, Helped greatly with homework. AN Amna Nadeem Aug 16,