An actual yieldThe actual mass of a product made in a chemical reaction. is the mass of a product actually obtained from the reaction. It is usually less than the theoretical yieldThe maximum possible mass of a product that can be made in a chemical reaction.. The reasons for this include:
incomplete reactions, in which some of the reactants do not react to form the product
practical losses during the experiment, such as during pouring or filteringThe process of passing a mixture through a device - soluble substances pass through the filter as a 'filtrate' but insoluble substances or unwanted material will stay in the filter as a 'residue'.
side reactions (unwanted reactions that compete with the desired reaction)
Calculating percentage yield
The percentage yieldA measure of how much product is actually made, calculated from: 100 × (actual yield) ÷ (theoretical yield). is calculated using this equation:
Copper oxide reacts with sulfuric acid to make copper sulfate and water. In an experiment, 1.6 g of dry copper sulfate crystals are made. If the theoretical yield is 2.0 g, calculate the percentage yield of copper sulfate.