Maximum amount of a specified product that could be obtained from specified amounts of reactants, assuming complete consumption of limiting reactant according to only one reaction and complete recovery of product. 
By Anne Marie Helmenstine, Ph.D. Percent Yield Definition: Percent yield is calculated to be the experimental yield divided by theoretical yield multiplied by 100%. In chemistry, we have theoretical yield, which is the amount of the product calculated from the limiting reactant. The limiting reactant is the reactant in the chemical reaction which limits the amount of product that can be formed. Example 2. Sometimes, you will also need to calculate the theoretical yield from the given chemical reaction. To do this, you will need to convert the amount of your limiting reactant into the amount of your final product. Let's take a look at how this is done with this problem. In chemistry, the reaction yield is the amount of product produced by a chemical reaction. The theoretical yield is the maximum amount of product that can be produced in a perfectly efficient reaction. Definition of Theoretical Yield. Maximum amount of a specified product that could be obtained from specified amounts of reactants, assuming complete consumption of limiting reactant according to only one reaction and complete recovery of product. (Compare with Actual Yield). Search the Dictionary. Percent Yield Definition. Percent yield is a measure of the efficiency of a chemical reaction. Adrianna Williams, Getty Images. Anne Marie Helmenstine, Ph.D. Chemistry Expert
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