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360 399.9. percentage yield = x 100 = 90.0%. HIGHER GRADE CHEMISTRY CALCULATIONS. Percentage yield is calculated using the formula:- percentage yield = x 100 The actual yield is given in the question.
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360 399.9 percentage yield = x 100 = 90.0% HIGHER GRADE CHEMISTRY CALCULATIONS Percentage yield is calculated using the formula:- percentage yield = x 100 The actual yield is given in the question. The theoretical yield is calculated from the balanced equation. actual yield theoretical yield Calculation of percentage yield. Worked example. In a reaction 320 kg of sulphur dioxide reacted with oxygen to form 360kg of sulphur trioxide. Calculate the percentage yield. Find the theoretical yield using the balanced equation:- 2SO2 + O2 2SO3 2 mol 2 mol 128.2 g 160.2 g 128.2 kg 160.2 kg 320 kg 399.9 kg
0.66 2.83 percentage yield = x 100 = 23.32% Calculation of percentage yield. • Calculations for you to try. • 0.5 tonnes of hydrogen reacts with excess nitrogen to form • 0.66 tonnes of ammonia. • N2 + 3H2 2NH3 • Calculate the percentage yield of ammonia. N2 + 3H2 2NH3 3 mol 2 mol 6 g 34 g 6 tonnes 34 tonnes 0.5 tonnes 2.83 tonnes Higher Grade Chemistry
170 230 percentage yield = x 100 = 73.9% Calculation of percentage yield. Calculations for you to try. 2. Ethene reacts with steam to ethanol C2H4 + H2O C2H5OH Calculate the percentage yield of ethanol when 140g of ethene reacts to form 170 g of ethanol. C2H4 + H2O C2H5OH 1 mol 1 mol 28 g 46 g 140 g 140/28 x 46 g 230 g Higher Grade Chemistry