16.4 g of Ca(OH)2 was reacted with HCl in a reaction. What was the expected mass of CaCl2, given the mass of the reactant Ca(OH)2 was 12.6 g? What is the percentage yield of the reaction? ( Give all answers to 3 significant figures)
Ca(OH)2:Mass = 12.6 g Molar mass= 40.1 + (16 x 2) + (1 x 2) = 74.1 g/molMoles = Mass / Molar mass = 12.6 g / 74.1 g/mol = 0.17 molThe molar ratio is 1:1 of Ca(OH)2 : CaCl2. ( 1 molecule of Ca(OH)2 reacts with 1 molecules of CaCl2).CaCl2:Moles = 0.17 molMolar mass = 40.1 + (35.5 x 2) = 111.1 g/molMass = Moles x Molar mass = 0.17 mol x 111.1 g/mol = 18.9 gPercentage yield:(Actual mass / Theoretical mass) x 100 = Percentage yield(16.4 g/18.9 g) x 100 = 86.8 %
