THE MOLE - PART 2 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Which one of the following statements is a quantitative observation? a. The freezing point of the clear and colourless solution was 40.5 C. b. The reactant demonstrated a high degree of viscosity. c. The overall reaction was exothermic. d. The product was yellow in colour. e. A brown-coloured gas evolved from the test tube. 2. Which of the following statements is true if 10.0 g of substance A reacts with 15.0 g of substance B? a. Substance A is the limiting reagent. b. Substance B is the limiting reagent. c. Substance A is the excess reagent. d. Substance B is the excess reagent. e. not enough information 3. Which of the following scenarios does NOT represent a quantitative analysis? a. A chemist tests a sample of water for the presence of chloride ions. b. A police officer uses a breathalyzer to measure the amount of alcohol in exhaled air. c. A lifeguard tests a sample of water to see how much disinfectant is present in the water. d. A sample of soil from a farm is tested for dangerously high levels of bacterial content. e. all of the above 4. Which of the following is not always conserved in a chemical reaction? a. total number of atoms d. energy b. total number of molecules e. none of the above are conserved c. mass 5. Ammonia can be manufactured using the Haber process. Determine the coefficient of H 2 when the following equation is correctly balanced: H + N 2 2 NH 3 a. 1 d. 4 b. 2 e. 5 c. 3 6. Consider the following equation: Al O 2 3 + H 2 Al + H2 O When this equation is correctly balanced, the coefficient of a. Al2O3 will be 2 d. will be 2 b. Al2O3 will be 3 e. H2O will be 3 c. H will be 1 2 7. Consider the following equation: Cl 2 + AlBr 3 Br 2 + AlCl3 When this equation is correctly balanced, the coefficient of Br 2 will be a. 1 d. 2 b. 3 e. 4 c. 5 8. Consider the following equation: Ba(NO 3) 2 + Fe 2(SO 4) 3 BaSO + Fe(NO ) When this equation is correctly balanced, the coefficient of a. Ba(NO 3) 2will be 4 d. BaSO 4will be 4 b. Ba(NO 3) 2will be 3 e. Fe(NO 3) 3will be 4 c. Fe (SO ) will be 2 2 4 3 4 3 3
9. The combustion of any hydrocarbon always yields carbon dioxide and water. Determine the coefficient of the hydrocarbon when the following equation is correctly balanced: C 5H 12 + O 2 CO 2 + H2O a. 8 d. 1 b. 5 e. 3 10. Consider the following equation: Fe + CuSO 4 Cu + FeSO 4. When this equation is correctly balanced, a. the coefficient of Fe will be 1 b. the coefficient of Cu will be 1 c. the coefficient of FeSO 4 will be 1 d. the coefficient of CuSO 4 will be 1 e. all of the above 11. Determine the sum of all the reactant coefficients when the following equation is balanced: H3PO 4 + BaCO 3 Ba(PO 3 4) 2 + H2O + CO2 a. 8 d. 5 b. 9 e. 2 12. The skeleton equation representing the neutralization of aluminum hydroxide with hydrochloric acid is Al(OH) 3 + HCl AlCl 3 + H2O. The coefficient of HCl in the balanced equation is a. 1 d. 7 b. 3 e. 9 13. Consider the following equation: NaHCO 3 + H2SO 4 NaSO 2 4 + H2O + CO2 When this equation is properly balanced, the coefficients for the substances in the equation are, in order from left to right, a. 2, 1, 1, 2, 2 d. 2, 1, 1, 1, 3 b. 1, 2, 2, 1, 1 e. 1, 2, 2, 1, 1 c. 2, 1, 2, 2, 2 14. When the equation KNO 3 + Pb 2(SO 4) 3 Pb(NO 3) 3 + K2SO 4is balanced, the sum of all the coefficients in the equation is a. 4 d. 14 b. 6 e. 18 c. 12 15. The balanced chemical equation for the combustion of methane gas is a. 2CH 4 + O 2 2CO 2 + H2O b. C H 4 + 2O 2 CO 2 + H2O c. C H 4 + 2O 2 CO 2 + 2H2O d. 2 C 2H 6 + 7O 2 4CO 2 + 6H2O e. C 2H 6 + 7O 2 2CO 2 + 3H2O 16. One way to produce oxygen gas is via the decomposition of potassium chlorate, as shown in the equation KClO 3 KCl + O 2. When properly balanced, the sum of all the coefficients is a. 3 d. 10 b. 6 e. 11 c. 7
17. When a piece of solid zinc is placed into a solution of hydrochloric acid, the resulting products are a diatomic gas and zinc chloride. The balanced equation for this reaction is a. Zn (s) + HCl (aq) ZnCl 2(aq) + H2(g) b. 2Zn (s) + 2HCl (aq) 2ZnCl (aq) + H2(g) c. Zn (s) + 2HCl (aq) ZnCl 2(aq) + H2(g) d. Zn (s) + 2HCl (aq) ZnCl (aq) + H2(g) e. 3Zn (s) + HCl (aq) 3ZnH 2(aq) + Cl2(g) 18. When copper is combined with a solution of silver nitrate, the resulting products are copper(ii) nitrate and silver. The balanced equation for this reaction is a. Cu + 2AgNO 3 Cu(NO 3) 2 + 2Ag b. 3Cu + 3AgNO 3 3Cu(NO 3) 2 + 3Ag c. 2Cu + 2AgNO 3 2CuNO 3 + 2Ag d. Cu + 2AgNO 3 CuNO 3 + 2Ag e. 2Cu + 2AgNO 3 2Cu(NO 3) 2 + 2Ag 19. Consider the following equation: + + To complete this balanced nuclear equation, the missing nuclear particle would be: a. d. b. e. c. 20. Stoichiometry is defined as a. mass and volume relationships in physical changes b. the relationship between the number of moles of a substance and the mass of the same substance c. mass and volume relationships in chemical changes d. the formation of a polymer from monomers e. the concept that energy is transferred in discrete units 21. The limiting reagent of a chemical reaction is a. the reactant of a chemical process that is not consumed completely b. the product of a chemical process that is consumed completely c. the product of a chemical process that is not consumed completely d. the reactant of a chemical process that is consumed completely e. none of the above 22. Ammonia is produced from a reaction as shown in the equation H 2(g) + 3N 2(g) 2NH 3(g). The number of moles of hydrogen required to produce 12 moles of ammonia is a. 1 d. 8 b. 3 e. 12. The reaction between hydrazine and hydrogen peroxide is shown in the balanced chemical equation N2H4 + 7 H2O 2 2 HNO 3 + 8 H2O. If 4.0 moles of hydrazine were used up in the reaction, the number of moles of water produced would total a. 2 d. 16 b. 7 e. 32 c. 8
24. Ethane burns in oxygen to produce carbon dioxide and water. The balanced chemical equation is 2C2H 6 + 7O 2 4CO 2 + 6H2O. The molar ratio between the ethane and water is a. 1:2 d. 7:4 b. 2:7 e. 4:7 c. 1:3 25. Sodium phosphate, Na3PO 4, can be prepared by combining sodium hydroxide and hydrogen phosphate as shown in the following balanced chemical equation: 3NaOH + H3PO 4 N a 3PO 4 + 3H2O If 2.5 mol of H3PO4 are reacted, the number of moles of water that will be produced is a. 1.0 d. 5.0 b. 2.5 e. 7.5 c. 3.0 26. Potassium chloride and oxygen gas are formed upon heating potassium chlorate. The following balanced equation shows this decomposition process: 2KClO 3 2KCl + 3O 2 The number of moles of KClO 3 required to produce 5.0 mol of oxygen is a. 1.0 d. 3.3 b. 2.0 e. 5.0 c. 3.0 27. Carbon dioxide and water are produced when ethanol, C2H5OH, is burned in oxygen. The number of moles of CO 2 that is produced when burning 6.0 mol of ethanol is a. 1.0 d. 12.0 b. 3.0 e. 15.0.0 28. Determine the number of grams of HCl needed to react completely with 12.8 g of aluminum, according to the following equation: 2Al + 6HCl 2AlCl 3 + 3H2 a. 51.9 g d. 103.8 g b. 17.3 g e. 38.4 g c. 34.6 g 29. Determine the number of grams of CO 2 that can be produced from 48.0 g of the hydrocarbon C3H 6, according to the following equation: 2C3H 6 + 9O 2 6CO 2 + 6H2O a. 37.6 g d. 151 g b. 50.2 g e. 188.4 g c. 87.8 g 30. Determine the mass of magnesium hydroxide that will react completely with 3.5 g of HCl in the following reaction: Mg(OH) 2 + 2HCl MgCl 2 + 2H2O a. 2.8 g d. 7.1 g b. 4.1 g e. 7.7 g c. 5.6 g 31. Determine the number of moles of silver that are produced when 210 g of silver nitrate are completely reacted as shown in the following reaction: Sn + 2 AgNO 3 2 Ag + Sn(NO 3) 2 a. 1.24 mol d. 3.11 mol b. 1.78 mol e. 4.07 mol c. 2.48 mol
32. When cobalt(ii) chloride is allowed to react with sodium hydroxide, the resulting products are cobalt(ii) hydroxide and sodium chloride. Determine the mass of cobalt(ii) chloride required to completely react with 56.9 g of sodium hydroxide. a. 185 g d. 139 g b. 92.3 g e. 205 g c. 46.3 g 33. How many oxygen molecules are produced when 89.5 g of mercury(ii) oxide are allowed to decompose according to the following equation: 2HgO 2Hg + O 2 a. 2.48 10 molecules d. 1.02 10 molecules b. 2.11 10 molecules e. 6.02 10 molecules c. 1.24 10 molecules 34. Determine the number of moles of water produced if 4.0 mol of O 2 are completely reacted according to the following balanced equation: 2C3H 6 + 9O 2 6CO 2 + 6H2O a. 1.5 mol d. 4.8 mol b. 1.9 mol e. 6.0 mol c. 2.7 mol 35. Determine the number of moles of chlorine, Cl 2, that are required to form 2.50 mol of lithium chloride, LiCl, according to the following equation: 2LiI + Cl 2 2LiCl + I 2 a. 2.00 mol d. 1.25 mol b. 1.75 mol e. 1.00 mol c. 1.50 mol 36. Zinc and sulphur react to form zinc sulfide, as shown in the following balanced chemical equation: Zn + S ZnS If 8.00 g of zinc and 8.00 g of sulphur are available for this reaction, the limiting reagent will be a. zinc d. both zinc and sulphur b. sulphur e. cannot be determined c. zinc sulfide 37. When calcium is allowed to react with nitrogen, N 2, calcium nitride is formed, as shown in the following balanced chemical equation: 3Ca + N 2 CaN 3 2 If 24.0 g of calcium and 12.0 g of nitrogen are available for this reaction, the limiting reagent will be a. calcium b. nitrogen c. calcium nitride d. both calcium and nitrogen will be consumed completely e. cannot be determined 38. Consider the following balanced chemical equation: Mg(OH) 2 + 2HCl MgCl 2 + 2H2O If 3.00 g of magnesium hydroxide and 5.50 g of HCl are available for the reaction, the reagent in excess is a. magnesium hydroxide d. water b. hydrochloric acid e. not enough information c. magnesium chloride
39. If 2.0 mol of aluminum are allowed to react with 2.8 mol of bromine, determine which of the statements below is true, given the following balanced equation: 2Al + 3Br 2 2AlBr 3 a. The aluminum will react completely. b. The bromine is the reagent in excess. c. The bromine is the limiting reagent. d. The aluminum is the limiting reagent. e. Both (a) and (d) are true. 40. Consider the following balanced equation: Al(OH) 3 + 3HCl AlCl 3 + 3H2O Determine the number of grams of aluminum chloride, AlCl 3, that are formed when 25.0 g of aluminum hydroxide reacts with 50.0 g of hydrochloric acid. a. 19.0 g d. 36.1 g b. 24.1 g e. 42.7 g c. 33.1 g 41. If 226.1 g of tin(ii) chloride was the actual amount obtained in a reaction for which the theoretical yield was 288.0 g, the percentage yield is a. 71.15% d. 84.11% b. 78.51% e. 86.77% c. 81.98% 42. In an experiment, 8.50 g of methane, CH 4, was reacted with 15.9 g of oxygen gas as shown in the following equation: CH 4(g) + 2O 2(g) CO 2(g) + 2H2 O(g) Determine the percentage yield if 9.77 g of carbon dioxide was obtained in the lab. a. 78.4% d. 87.1% b. 81.9% e. 89.4% c. 82.3%