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Putting it all together. Stoichiometry. Lesson Essential Question. How can the mass of products be determined from the amounts of the reactants in a chemical reaction?. STOICHIOMETRY -. The study of quantities of materials consumed and produced in chemical reactions. Mass-Mass Stoichiometry.
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Putting it all together Stoichiometry
Lesson Essential Question How can the mass of products be determined from the amounts of the reactantsin a chemical reaction?
STOICHIOMETRY - The study of quantities of materials consumed and produced in chemical reactions.
Mass-Mass Stoichiometry If 20.0 grams of zinc pellets reacts with excess hydrochloric acid, how many grams of zinc chloride are going to be produced? Zn(s) + 2 HCl(aq) ZnCl2(s) + H2(g) 1 1 1. Write a balanced equation. 20.0 g excess ? grams 65.39 g/mole 136.29 g/mole Write the “given” information from the problem under the corresponding chemical compound Write down any information necessary to change the given measurements to moles. (i.e. molar mass or molar volume at STP.) 20.0 g Zn 1 mole Zn 1 mole ZnCl2 136.29 g ZnCl2 = X X X 1 1 mole Zn 1 mole ZnCl2 65.39 g Zn 6. “Stoichiometry” Step. This step allows you to go from one compound to another “legally”. Only use the coefficients in front of the compounds involved in the problem Using the information under your “given” and convert grams to moles. 41.7 g ZnCl2 solid 4. Start the problem with your “given” over one. 7. Convert moles to appropriate answer unit and use the calculator to solve the problem.
Mass-Mass Stoichiometry 6.50 grams of aluminum foil reacts with excess oxygen, how many grams of aluminum oxide are going to be produced? 4 Al(s) + 3 O2(g) 2 Al2O3(s) 1. Write a balanced equation. 6.50 g excess ? grams 26.98 g/mole 101.96 g/mole Write the “given” information from the problem under the corresponding chemical compound Write down any information necessary to change the given measurements to moles. (i.e. molar mass or molar volume at STP.) 6.50 g Al 1 mole Al 2 mole Al2O3 101.96 g Al2O3 = X X X 12.28 g Al2O3 solid 1 4 mole Al 1 mole Al2O3 26.98 g Al Convert moles to the appropriate unit using gathered information, Calculate answer. Using the information under your “given” and convert grams to moles. 6. “Stoichiometry” Step. This step allows you to go from one compound to another “legally”. Only use the coefficients in front of the compounds involved in the problem 4. Start the problem with your “given” over one.
Mass-Volume Stoichiometry How many liters of oxygen gas, at STP can be collected from the complete decomposition of 50.0 g of potassium chlorate 2 KClO3(s) 2 KCl(s) + 3 O2(g) 1. Write a balanced equation. 50.0 g ? Liters at STP 122.55 g/mole 22.4 L/mole Write the “given” information from the problem under the corresponding chemical compound Write down any information necessary to change the given measurements to moles. (i.e. molar mass or molar volume at STP.) 50.0 g KClO3 1 mole KClO3 3 mole O2 22.4 L O2 = X X X 1 122.55 g KClO3 2 mole KClO3 1 mole O2 13.71 L O2 gas 6. “Stoichiometry” Step. This step allows you to go from one compound to another “legally”. Only use the coefficients in front of the compounds involved in the problem 4. Start the problem with your “given” over one. Using the information under your “given” and convert grams to moles. Convert moles to the appropriate unit using gathered information, Calculate answer.