nitrogen? 2) How many grams of ammonia are produced in the above reaction #1? 3) AgNO3 + ... g of silver nitrate reacting with an excess of barium chl...
Stoichiometry Notes (Ch. 9) A. Stoichiometry The study of __________________________________________________. B. Chemical Reaction
_________of propane reacts with __________of oxygen to produce __________of carbon dioxide and ___________of water and energy. C. Chemical Recipe (Chemical Equation) N2H4 + 2 H2O2 → N2 + 4 H2O ___________ also represent the # of ______. For every ___mole of N2H4, ___ moles of H2O2 are needed to make ___ mole of N2 and ___ moles of H2O. If you double the # of moles of H2O2, how many moles of N2H4 do you need? How many moles of water do you make? D. Mole-Mole -Use the ratio of ________ in the recipe (chemical equation) to determine how to modify the recipe. -Look up the _______________ for ratio. Ex. If you _______ an ingredient, you will ________ everything else. If you want to ________ the products, you must _______ the ingredients. E. Mole-Mole Example N2 + 3 H2 -> 2 NH3 1) How many moles of hydrogen are needed to completely react with two moles of nitrogen? 2 KClO3 -> 2 KCl + 3 O2 2) How many moles of oxygen are produced by the decomposition of six moles of potassium chlorate? Ms. Park
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Learning Check (Mole-Mole) Zn + 2 HCl -> ZnCl2 + H2 1) How many moles of hydrogen are produced from the reaction of four moles of zinc with an excess of hydrochloric acid?
C3H8 + 5 O2 -> 3 CO2 + 4 H2O 2) How many moles of oxygen necessary to react completely with five moles of propane (C3H8)? K3PO4 + Al(NO3)3 -> KNO3 + AlPO4 3) How many moles of potassium nitrate are produced when three moles of potassium phosphate react with three moles of aluminum nitrate? (Balance the equation first.)
F. ______________ (_________________________________________)
___________________________ ___________: ______________________ ___________: ______________________ ___________: ______________________ G. Mass-Mass
Ms. Park
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H. Mass-Mass Example 2 KClO3 -> 2 KCl + 3 O2 1) How many grams of potassium chloride are produced if 25 g of potassium chlorate decompose?
Learning Check (Mass-Mass) N2 + 3 H2 -> 2 NH3 1) How many grams of hydrogen are necessary to react completely with 75 g of nitrogen?
2) How many grams of ammonia are produced in the above reaction #1?
3) AgNO3 + BaCl2 -> AgCl + Ba(NO3)2 (Balance the equation.) How many grams of silver chloride are produced from 15 g of silver nitrate reacting with an excess of barium chloride?
4) How much barium chloride is necessary to react with the silver nitrate in #3?
I. Volume-Volume (at STP)
J. Volume-Volume Example 2 CO + O2 -> 2 CO2 1) How many liters of oxygen are necessary if 50 liters of carbon monoxide are burned at STP?
Ms. Park
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Learning Check (Volume-Volume) N2 + 3 H2 -> 2 NH3 1) What volume of hydrogen is necessary to react with ten liters of nitrogen to produce ammonia at STP?
2) What volume of ammonia is produced in the #1?
C3H8 + O2 -> 3 CO2 + 4 H2O 3) If 60 L of oxygen are consumed in the above reaction, how many liters of carbon dioxide are produced at STP?
2 H2O -> 2 H2 + O2 4) If 90 mL of hydrogen are produced, how many mililiters of oxygen are produced at STP?
K. Mixed Stoichiometry Examples 1) 2 AlCl3 -> 2 Al + 3 Cl2 If 30 g of AlCl3 are decomposed, how many molecules of Cl2 are produced?
2) Zn + 2 HCl -> ZnCl2 + H2 What volume of hydrogen at STP is produced when 10 g of zinc react with an excess of hydrochloric acid?
3) Zn + 2 HCl -> ZnCl2 + H2 What mass of hydrochloric acid is needed to react with 5 moles of zinc?
Learning Check (Mixed Stoichiometry) N2 + 3 H2 -> 2 NH3 1) What volume of NH3 at STP is produced if 75 g of N2 is reacted with an excess of H2?
Ms. Park
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H2SO4 + 2 NaOH -> H2O + Na2SO4 2) How many molecules of water are produced if 8 g of sodium sulfate are produced?
2 KClO3 -> 2 KCl + 3 O2 3) If 10 g of KClO3 is decomposed, what volume of O2 is produced at STP?
4) How many grams of KCl are produced in #3?
5) How many liters of O2 is produced when 8 moles of KClO3 is decomposed at STP?
L. Limiting Reactant -Limiting Reactant _____________________________ _____________________________ -Excess Reactant _____________________________________ _____________________________________ cheaper & easier to recycle 1. For each reactant, calculate the amount of product formed by _______________________________ calculation. (A = each reactant; B=one same product) 2. Circle ________ answer. The reactant w/ _____________is the limiting reactant. The smaller answer is the possible _______________________ M. Limiting Reactant Example 1) 79.1 g of zinc react with 85 g HCl. Identify the limiting and excess reactants. How many liters of hydrogen are formed at STP? Zn + 2HCl ZnCl2 + H2
Ms. Park
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N2 + 3 H2 -> 2 NH3 2) How many grams of NH3 can be produced from the reaction of 28 g of N2 and 25 g of H2?
Learning Check (Limiting Reactant) Mg + 2 HCl -> MgCl2 + H2 1) What volume of hydrogen at STP is produced from the reaction of 50 g of Mg and the equivalent of 75 g of HCl?
Ms. Park
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3 AgNO3 + Na3PO4 -> Ag3PO4 + 3 NaNO3 2) Silver nitrate and sodium phosphate are reacted in equal amounts of 200 g each. How many grams of silver phosphate are produced?
N. Percent Yield
% yield =
Actual value is always _________ in a Q. Theoretical value could be _______ or it is ___________ using mass-mass.
M. Percent Yield Example 1) When 45.8 g of K2CO3 react with excess HCl, 46.3 g of KCl are formed. Calculate the theoretical and % yields of KCl. K2CO3 + 2HCl 2KCl + H2O + CO2
