Pre AP Chemistry Chapter 9 Practice Set Show your work for all problems.
Exercise 1
For questions 1-4 use the equation: 4NH3 + 6NO 5N2 + 6H2O 1. Calculate the moles of NH3 required to react with 15.0 moles of NO. 2. Calculate the moles of nitrogen produced from 7.5 moles of NO. 3. Calculate the moles of NO required to produce 0.65 moles of nitrogen. 4. Calculate the moles of water produced from 11.2 moles of NO.
5. Calculate the number of moles of oxygen needed for the complete combustion of 5.00 moles of vitamin C. C6H8O6 + 5O2 6CO2 + 4H2O
6. A sample of 0.2500 moles of solid potassium chlorate is heated gently for a period of time and 0.2000 moles of the compound decomposes. Calculate the number of moles of oxygen gas that is produced. KClO3 KCl + O2
7. How many moles of oxygen are required to burn 4.8 moles of butane? 2C4H10 + 13O2 8CO2 + 10H2O
8. Sodium chloride (0.400 mol) is allowed to react with an excess of sulfuric acid. How many moles of hydrogen chloride could be formed? NaCl + H2SO4 Na2SO4 + HCl
9. If 0.380 mol of barium nitrate is allowed to react with an excess of phosphoric acid, how many moles of barium phosphate could be formed? Ba(NO3)2 + H3PO4 Ba3(PO4)2 + HNO3
10. How many moles of hydrogen molecules could be produced by the reaction of 3.40 moles of sodium atoms with water? Na + H2O NaOH + H2
11. How many moles of HI would be necessary to produce 2.20 moles of iodine, according to the following balanced equation? 10HI + 2KMnO4 + 3H2SO4 5I2 + 2MnSO4 + K2SO4 + 8H2O
12. V2O5 + Cl2 VOCl3 + O2 a. How many moles of V2O5 are required to produce 7.0 moles of VOCl3? b. How many moles of O2 are produced from 5.0 moles of V2O5 c. How many moles of Cl2 are required to produce 6.0 moles of VOCl3? d. How many moles of V2O5 are required to produce 4.0 moles of O2? Exercise 2
For questions 1-14 use the equation: 2Mg + O2 2MgO
1. Calculate the number of moles of oxygen needed to react with 6.00 moles of Mg. 2. Calculate the number of moles of MgO produced when 0.4 moles of oxygen react. 3. Calculate the number of moles of MgO produced when 32 g of oxygen react. 4. Calculate the grams of oxygen needed to produce 6 g of MgO.
For questions 5-9 use the equation: 2C6H6 + 15O2 12CO2 + 6H2O
5. Calculate the number of moles of oxygen required to react with 5.00 moles of C6H6. 6. Calculate the moles of CO2 produced when 0.75 moles of O2 react. 7. Calculate the number of grams of C6H6 needed to produce 50.0 g of water. 8. Calculate the number of moles of water produced when 75 g of oxygen react. 9. Calculate the grams of C6H6 needed to produce 25 g of CO2.
10. Calculate the number of grams of H2SO4 produced when 27 g of water react with an excess of SO3. H2O + SO3 H2SO4
11. Calculate the number of molecules of oxygen produced when 34.0 g of water decomposes.
12. How many molecules of chlorine are produced when 40.0 g of salt is split by electrolysis?
13. Calculate the mass of copper that is formed when 15.0 g of aluminum reacts with excess copper (II) sulfate.
14. Calculate the number of grams of oxygen that can be produced by completely decomposing 15 g of mercury (II) oxide.
15. Calculate the number of grams of carbon dioxide produced from the burning of 1.65 moles of C3H8. C3H8 + 5O2 3CO2 + 4H2O
16. Calculate the number of grams of zinc chloride that can be prepared from 34.0 g of zinc. Zn + 2HCl ZnCl2 + H2
17. Calculate the number of grams of hydrogen that can be produced from 6.80 g of aluminum. 2Al + 6NaOH 2Na2AlO2 + 3H2 18. How many grams of silver chloride can be prepared from 78.0 g of silver nitrate? AgNO3 + NaCl AgCl + HNO3
19. If 4.00 g of Bi react with an excess of F2, determine the yield of BiF3. 3Bi + 3F2 2BiF3
20. Calculate the number of moles of barium sulfate that can be prepared from 60.0 g of barium chloride. BaCl2 + Na2SO4 BaSO4 + NaCl
21. Calculate the number of moles of calcium chloride that would be necessary to prepare 85.0 g of calcium phosphate. CaCl2 + Na3PO4 Ca3(PO4)2 + NaCl
22. How many grams of chlorine gas must be reacted with excess sodium iodide if 10.0 grams of sodium chloride are needed?
23. What mass of copper is required to replace silver from 4.00 g of silver nitrate?
24. How much silver phosphate is produced if 10.0 g of silver acetate react with excess sodium phosphate?
25. If excess ammonium sulfate reacts with 20.0 g of calcium hydroxide, how many grams of ammonia are produced? The other products are water and calcium sulfate.
Exercise 3 1. Given the following balanced equation: 5 H2 + F2 H2F2 + 5.27 x 10 J Calculate the number of joules of heat energy produced in the reaction of 37.0 g of fluorine gas with sufficient hydrogen gas.
2. Given the following balanced equation: 4 O2 + 2F2 + 4.60 x 10 J 2OF2 Calculate the number of grams of fluorine gas needed for the reaction with 8.74 x 103 J of heat energy and sufficient oxygen gas.
3. The overall reaction in commercial heat packs can be represented as 4Fe + 3O2 2Fe2O3 + 1,652 kJ How much heat is released when 1.00 g of iron is reacted with excess oxygen?
4. Consider the combustion of propane: C3H8 + 5O2 3CO2 + 4H2O + 2,221 kJ Assume that all the heat comes from the combustion of propane. What mass of propane must be burned to furnish this amount of energy assuming the process is 60.% efficient? 5. Consider the following reaction: 2Mg + O2 2MgO + 1,204 kJ How many grams of MgO are produced when 96.0 kJ of heat are produced?
Exercise 4 1. Suppose a 2.00 g sample of potassium chlorate is heated and 0.35 g of oxygen was collected as a result of the decomposition. What is the % yield of the reaction? 2KClO3 2KCl + 3O2
2. Calculate the percent yield in the electrolytic decomposition of hydrogen chloride if 25.8 g of HCl produce 13.6 g of chlorine gas. 2HCl H2 + Cl2
3. Calculate the actual yield for the production of ammonia gas from hydrogen and nitrogen gases if the percent yield is 68.2% and you begin with 2.00 kg of nitrogen gas. N2 + 3H2 2NH3
4. Calculate the percent yield when 24.8 g of C3H8 are burned in air to produce 15.0 g of water vapor. C3H8 + 5O2 3CO2 + 4H2O
5. What is the actual amount of magnesium oxide that can be produced when carbon dioxide reacts with 42.8 g of magnesium metal? The percent yield for this reaction is 81.7%. 2Mg + CO2 2MgO + C
6. The percentage yield of a reaction is 73.7%. How many grams of Al must be used to react with an excess of H3PO4 to give 30.0 g of AlPO4?
7. Freon-12, CCl2F2, is prepared by CCl4 reacting with HF. HCl is the other product of this reaction. What is the percent yield of a reaction in which 12.5 g of CCl2F2 is produced from 32.9 g of CCl4?
8. Chlorobenzene, C6H5Cl, is manufactured on a large scale to produce such useful compounds as aspirin, oil of wintergreen, insecticides, and disinfectants. A particular industrial reactor produced chlorobenzene by this reaction in 73.0% yield. What mass of benzene, in kg, would be required to produce 775 kg of chlorobenzene? C6H6 + Cl2 C6H5Cl + HCl
9. Calculate the percent yield if 125 g of NaClO3 were heated and produced 50.0 g of NaCl. 2NaClO3 2NaCl + 3O2
10. Suppose 50.0 g of TiO2 is reacted with excess chlorine and carbon and 55.0 g of TiCl4 is obtained. Compute the percentage yield of TiCl4. TiO2 + 2Cl2 + 2C TiCl4 + 2CO 11. Ethyl propionate has a pineapple-like odor and is used as a flavoring agent in fruit syrup. In an experiment 349 g of ethyl propionate was obtained from 250. g of ethanol, with propionic acid in excess. Calculate the percentage yield of this reaction. C2H5OH + C2H5CO2H C2H5O2CC2H5 + H2O
12. When 9.00 g of Al react with an excess of H3PO4, 30.0 g of AlPO4 are produced. What is the percent yield of this reaction? 2Al + 2H3PO4 2AlPO4 + 3H2
13. How many grams of C2H2 is produced if 2.0 g of hydrogen gas reacts with carbon that results in a 92.0% yield? 2C + H2 C2H2
14. What mass of ammonium chloride is produced if 5.00 g of ammonia reacts with excess hydrochloric acid with a 95.0% yield? NH3 + HCl NH4Cl
Exercise 5
1. Aluminum combines with iodine according to the following equation. How many grams of AlI3 can be formed when 1.00 g of aluminum reacts with 12.00 g of iodine? 2Al + 3I2 2AlI3
2. Zinc and sulfur react to for zinc sulfide, a substance used in phosphors that coat the inner surface of TV tubes. How many grams of ZnS can be formed when 12.0 g of Zn react with 6.50 g of S? Zn + S ZnS
3. What mass of PbI2 will precipitate when 2.57 g Pb(NO3)2 react with 2.28 g of KI? Pb(NO3)2 + 2KI PbI2 + 2KNO3
4. The mass of iron produced by the reaction of 7.00 kg of Fe2O3 and 3.00 kg of CO is 3.55 kg. What is the percent yield? Fe2O3 + 3CO 2Fe + 3CO2
5. The mass of H2 produced by reaction of 1.60 g Fe and 2.00 g HCl is 0.0505 g. What is the percent yield? Fe + 2HCl FeCl2 + H2
6. The mass of H2 produced by reaction of 1.80 g Al and 6.00 g H2SO4 is 0.112 g. What is the percent yield? 2Al + 3H2SO4 Al2(SO4)3 + 3 H2 7. How many kilograms of potassium nitrate will be produced from 50.0 kg of potassium chloride and 50.0 kg of nitric acid? An important by-product is chlorine. How many kilograms of chlorine will be produced? 4KCl + 4HNO3 + O2 4KNO3 + 2Cl2 + 2H2O
8. Suppose that 60.0 g of sodium hydroxide is added to 20.0 g of sulfuric acid. How many grams of sodium sulfate will be produced? 2NaOH + H2SO4 Na2SO4 + 2H2O
Exercise 6 1. Calculate the amount of excess reagent when 3.1 mol of SO2 react with 2.7 mol of oxygen. 2SO2 + O2 2SO3
2. What is the limiting reagent when 100 g of H3PO4 react with 25.0 g Al?
3. Calculate the moles of excess reagent when 4.0 moles of CH4 react with 4.00 mol of O2. CH4 + 2O2 CO2 + 2H2O
225 g of zinc reacts with 275 g of H2SO4 to produce 1.50 g of hydrogen. Zn + H2SO4 ZnSO4 + H2 4. Identify the excess reagent. 5. Identify the limiting reagent. 6. What is the theoretical yield of hydrogen? 7. What is the actual yield of hydrogen? 8. What is the amount of zinc at the end of the reaction? 9. What is the amount of sulfuric acid at the end of the reaction? 10. What is the percent yield of the reaction?
170.0 g of NH3 reacts with 300.0 g of NaClO to produce 105 g of N2H4. 2NH3 + NaClO N2H4 + H2O + NaCl 11. Identify the excess reagent. 12. Identify the limiting reagent. 13. What is the theoretical yield of N2H4? 14. What is the actual yield of N2H4? 15. What is the percent yield of N2H4? 16. How much NH3 will remain at the end of the reaction? 17. How much NaClO will remain at the end of the reaction?
18. Cupric sulfide (0.610 mol) is treated with 1.40 mol of nitric acid. (a) How many moles of cupric nitrate could be produced? (b) If 0.500 mol of cupric nitrate is actually obtained, what is the percent yield? (c) Calculate the number of moles of excess reagent remaining at the end of the reaction. 3CuS + 8HNO3 3Cu(NO3)2 + 2NO + 4H2O + 3S 19. A 1.4 g sample of magnesium is treated with 8.3 g of sulfuric acid. (a) How many grams of hydrogen could be produced? (b) If 0.060 g of hydrogen is actually obtained, what is the percent yield? (c) Calculate the number of moles of excess reagent remaining at the end of the reaction. Mg + H2SO4 MgSO4 + H2
20. Iron (II) hydroxide (3.20 mol) is treated with 0.270 mol of H3PO4. (a) How many grams of iron (II) phosphate could be produced? (b) If 34.0 g of iron (II) phosphate is actually obtained, what is the percent yield? (c) Calculate the number of moles of excess reagent remaining at the end of the reaction. 3Fe(OH)2 + 2H3PO4 Fe3(PO4)2 + 6H2O