Tuesday, Oct. 15th: “A” Day Wednesday, Oct. 16th: “B” Day Agenda Ch 9 review: Questions/problems? Jeopardy Review Homework: Vocabulary Crossword Puzzle Next time: Ch 9 test: “Stoichiometry” Concept review packets/puzzles due Ch 9 Review Questions/problems? Ch. 9 Short Answer Test Questions The questions in the “critical thinking” category are 5 of the 6 short answer questions that will be on the chapter test… The 6th question is also in the game, just not in this category… Stoichiometry Ch.#9 THE RULES: • You will be in five teams • The winning team will receive mole money • The host’s decisions are final And now…here is the host of Jeopardy… Mrs. Elfline Let’s Get Ready to play… Today’s Categories are: Vocabulary Moles/Grams Volume/Particles Critical Thinking Calculations! Movie Quotes Vocabulary Moles/Grams Volume/Particles Critical Thinking Calculations! Movie Quotes $100 $100 $100 $100 $100 FJ $200 $200 $200 $200 $200 $300 $300 $300 $300 $300 $400 $400 $400 $400 $400 $500 $500 $500 $500 $500 DD The substance not completely used up in a chemical reaction Answer… Excess Reactant 100 The branch of chemistry that deals with the relationship between reactants and products in a chemical reaction Answer… Stoichiometry 200 The substance that controls the amount of product that can be made Answer… Limiting Reactant 300 The measured amount of product obtained from a chemical reaction Answer… Actual Yield 400 The ratio of the actual yield to theoretical yield X 100% Answer… Percentage Yield 500 The ratio of Fe to Fe2O3 in the reaction below is Fe2O3 + 2 Al 2 Fe + Al2O3 Answer… 2:1 (2 to 1) 100 To convert from moles of what you’re given to moles of what you want, what do you need to use? Answer… Mole Ratio (aka secret magic step) 200 How is density used in stoichiometry problems? Answer… Use the density of the substance to convert mL or liters of what you’re given to grams and then to moles. Then you can use the mole ratio to convert to moles of what you want to find. 300 What number do you need to convert to number of atoms/molecules/particles? Answer… 23 10 6.022 X particles/mole (Avogadro’s number) 400 Why must a chemical equation be balanced to solve stoichiometry problems? Answer… The coefficients in a balanced chemical equation show the relative number of moles of each substance. Mole ratios can then be found and used to convert from moles of one substance to moles of another. 500 Why must a chemical equation be balanced to solve stoichiometry problems? Answer… The coefficients from a balanced chemical equation represent the relative number of moles and are used in the mole ratio conversion step. 100 Explain the difference between a limiting reactant and an excess reactant. Answer… The limiting reactant controls the amount of product that can be made and will be used up in the reaction. The excess reactant will be left over after the reaction. 200 How does the actual yield of a chemical reaction compare to the theoretical yield? Answer… The actual yield is LESS than the theoretical yield. 300 Explain why the conversion factor 3 g Mg(OH)2 cannot be used 6 g H2O for the following reaction: Mg3N2 + 6 H2O 3 Mg(OH)2 + 2 NH3 Answer… The coefficients from the balanced equation represent number of moles of reactants and products – NOT grams. 400 In the “Stoichiometry and Gravimetric Analysis” lab, you prepared strontium carbonate, SrCO3, according to the following equation: SrCl2 + Na2CO3 2 NaCl + SrCO3 a) What type of reaction was this? b) Why was the SrCO3 rinsed in the funnel after filtering? Answer… a) Double displacement b) The SrCO3 was rinsed in the funnel to remove any NaCl that may have been present. 500 How many moles of hydrogen are needed to prepare 312 moles of ammonia? N2 + 3 H2 2 NH3 Answer… 468 mol H2 100 How many grams of Al are needed to completely react with 135 g of Fe2O3? Fe2O3 + 2 Al 2 Fe + Al2O3 Answer… 45.6 g Al 200 How many mL of C5H8 can be made from 366 mL of C5H12? (Density of C5H8 = 0.681 g/mL) (Density of C5H12 = 0.620 g/mL) C5H12 C5H8 + 2 H2 Answer… 315 mL C5H8 300 How many grams of C5H8 form from 1.89 X 1024 molecules C5H12? C5H12 C5H8 + 2 H2 Answer… 214 g C5H8 400 Find the limiting reactant, the theoretical yield, and the percentage yield if 14.0 g N2 are mixed with 9.0 g H2 and 16.1 g NH3 form. N2 + 3 H2 2 NH3 Answer… N2 is limiting reactant Theoretical yield = 17.0 g NH3 Percentage yield = 94.7% 500 Listen… What movie is this quote from? Answer… “The Wizard of Oz” “I’ll get you my pretty, and your little dog too!” (The wicked witch of the west talking to Dorothy) 100 Listen… What movie is this quote from? Answer… “Toy Story” “reach for the sky” (What Woody says when his string is pulled) 200 Listen… What movie is this quote from? Answer… “Dodgeball” “Nobody makes me bleed my own blood…nobody!” (What White Goodman, played by Ben Stiller, says after Taylor makes him bleed.) 300 Listen… What movie is this quote from? Answer… “Shrek” “I’m not a puppet, I’m a real boy!” (Pinocchio trying to convince himself that he’s a real boy) 400 Listen… What movie is this quote from? Answer… “Jaws” “You’re gonna need a bigger boat right?” (What sheriff Martin Brody says after he sees the size of the shark that’s terrorizing the citizens of Amity) 500 Daily Double How much do you want to wager? Daily Double FINAL JEOPARDY CATEGORY: Theoretical Yield How much do you want to wager? Proceed… Identify the limiting reactant and theoretical yield of H3PO3 if 225 g of PCl3 is mixed with 123 g of H2O. PCl3 + 3H2O H3PO3 +3HCl Proceed… Limiting Reactant = PCl3 Theoretical Yield = 134 g H3PO3 Proceed… Thanks for PLAYING! Credits Created by: Chad Kafka, Business Teacher Huntley High School [email protected] Jeopardy sound effects used solely for the purpose of fun, entertainment, and education and NOT for profit.