Moles, Mass, and Limiting Reactants Answers follow at end Interpreting a Chemical Equation) 1. How many moles of chlorine gas react with 1 mol of hydrogen gas according tothe balanced chemical equation? H 2 (g) + Cl 2 (g) 2 HCl(g) 1 mol 2 mol 3 mol 4 mol 2. Assuming similar conditions, how many liters of chlorine gas react to produce 2 L of hydrogen chloride gas? H 2 (g) + Cl 2 (g) 2 HCl(g) 1 L 2 L 3 L 4 L 3. How many moles of carbon monoxide react with 1 mol of oxygen gas accordingto the balanced chemical equation? 2 CO(g) + O 2 (g) 2 CO 2 (g) 1 mol 2 mol 3 mol 4 mol Page VII-9-1 / Limiting Reactant Worksheet II
4. Assuming similar conditions, how many liters of carbon monoxide gas react to produce 2 L of carbon dioxide gas? 2 CO(g) + O 2 (g) 2 CO 2 (g) 1 L 2 L 3 L 4 L 5. How many moles of water vapor, H 2 O, react with 1 mol of charcoal, C, according to the balanced chemical equation? C(s) + H 2 O(g) CO(g) + H 2 (g) 1 mol 2 mol 3 mol 4 mol 6. Assuming similar conditions, how many liters of water vapor, H 2 O, react to produce 1 L of hydrogen gas? C(s) + H 2 O(g) CO(g) + H 2 (g) 1 L 2 L 3 L 4 L 7. In an experiment, 5.585 g of iron metal reacts with 3.207 g of yellow sulfur. Using the conservation of mass law, predict the mass of product. Fe(s) + S(s) FeS(s) 2.198 g 2.378 g 4.396 g 8.792 g 17.584 g Page VII-9-2 / Limiting Reactant Worksheet II
8. In an experiment, 1.201 g of charcoal reacts with 6.414 g of powdered sulfur. Using the conservation of mass law, predict the mass of product. C(s) + 2 S(s) CS 2 (g) 4.408 g 5.213 g 7.615 g 8.816 g 14.029 g 9. In an experiment, 0.520 g of chromium metal reacts with 3.807 g of iodine. Using the conservation of mass law, predict the mass of product. 2 Cr(s) + 3 I 2 (s) 2 CrI 3 (s) 1.529 g 3.287 g 4.327 g 8.654 g 12.461 g 10. In an experiment, 0.243 g of magnesium reacts to give 0.403 g magnesium oxide. Using the conservation of mass law, predict the mass of reacting oxygen gas. 2 Mg(s) + O 2 (g) 2 MgO(s) 0.080 g 0.160 g 0.320 g 0.646 g 1.292 g 11. In an experiment, 0.327 g of zinc metal reacts to produce 0.407 g of zinc oxide. Using the conservation of mass law, predict the mass of reacting oxygen gas. 2 Zn(s) + O 2 (g) 2 ZnO(s) 0.040 g 0.080 g 0.160 g 0.734 g 1.468 g Page VII-9-3 / Limiting Reactant Worksheet II
12. In an experiment, 0.197 g of gold metal reacts to yield 0.303 g of gold(iii)chloride. Using the conservation of mass law, predict the mass of reacting chlorine gas. 2 Au(s) + 3 Cl 2 (g) 2 AuCl 3 (s) 0.035 g 0.106 g 0.318 g 0.167 g 0.500 g Mole Mole Relationships) 13. How many moles of iodine vapor react with of hydrogen gas? H 2 (g) + I 2 (g) HI(g) 4.00 mol 14. How many moles of hydrogen iodide are produced from ofiodine? H 2 (g) + I 2 (g) HI(g) 4.00 mol 15. How many moles of hydrogen gas react to yield of hydrogen iodide? H 2 (g) + I 2 (g) HI(g) 4.00 mol Page VII-9-4 / Limiting Reactant Worksheet II
16. How many moles of water are produced from of hydrogen peroxide? H 2 O 2 (l) H 2 O(l) + O 2 (g) 4.00 mol 17. How many moles of oxygen are produced from of hydrogenperoxide? H 2 O 2 (l) H 2 O(l) + O 2 (g) 4.00 mol 18. How many moles of hydrogen peroxide decompose to give of oxygen? H 2 O 2 (l) H 2 O(l) + O 2 (g) 4.00 mol 19. How many moles of oxygen gas react with NO? UV NO(g) + O 2 (g) NO 2 (g) 0.250 mol Page VII-9-5 / Limiting Reactant Worksheet II
20. How many moles of nitrogen dioxide gas are produced from NO? UV NO(g) + O 2 (g) NO 2 (g) 0.250 mol 21. How many moles of oxygen gas react to yield NO 2? UV NO(g) + O 2 (g) NO 2 (g) 0.250 mol 22. How many moles of water react with 5.00 mol of lithium metal? Li(s) + H 2 O(l) LiOH(aq) + H 2 (g) 2.50 mol 5.00 mol 10.0 mol 20.0 mol 23. How many moles of hydrogen gas are produced from 5.00 mol of water? Li(s) + H 2 O(l) LiOH(aq) + H 2 (g) 2.50 mol 5.00 mol 10.0 mol 20.0 mol Page VII-9-6 / Limiting Reactant Worksheet II
24. How many moles of lithium metal react to yield 5.00 mol of hydrogen gas? Li(s) + H 2 O(l) LiOH(aq) + H 2 (g) 2.50 mol 5.00 mol 10.0 mol 20.0 mol 25. How many moles of water react with of calcium metal? Ca(s) + H 2 O(l) Ca(OH) 2 (aq) + H 2 (g) 0.250 mol 26. How many moles of hydrogen gas are produced from of water? Ca(s) + H 2 O(l) Ca(OH) 2 (aq) + H 2 (g) 0.250 mol 27. How many moles of calcium metal react to yield of hydrogen gas? Ca(s) + H 2 O(l) Ca(OH) 2 (aq) + H 2 (g) 0.250 mol Page VII-9-7 / Limiting Reactant Worksheet II
28. How many moles of oxygen gas react with 0.100 mol of pentane, C 5 H 12? spark C 5 H 12 (g) + O 2 (g) CO 2 (g) + H 2 O(g) 0.100 mol 0.600 mol 0.800 mol 29. How many moles of water are produced from 0.100 mol pentane, C 5 H 12? spark C 5 H 12 (g) + O 2 (g) CO 2 (g) + H 2 O(g) 0.100 mol 0.600 mol 0.800 mol 30. How many moles of oxygen gas react to yield 0.100 mol water? spark C 5 H 12 (g) + O 2 (g) CO 2 (g) + H 2 O(g) 0.100 mol 0.600 mol 0.800 mol Mass Mole Mole Mass Problems) 31. What is the mass of silver metal produced from 6.35 g of copper? 0.187 g 0.540 g 0.747 g 1.08 g 21.6 g Cu(s) + AgNO 3 (aq) Cu(NO 3 ) 2 (aq) + Ag(s) Page VII-9-8 / Limiting Reactant Worksheet II
32. What is the mass of copper metal that yields 0.500 g of silver? 0.147 g 0.294 g 0.425 g 0.589 g 1.70 g Cu(s) + AgNO 3 (aq) Cu(NO 3 ) 2 (aq) + Ag(s) 33. What is the mass of silver bromide (187.77 g/mol) precipitated from 2.96 gof iron(iii) bromide (295.55 g/mol)? 0.940 g 0.627 g 1.88 g 5.64 g 3.76 g FeBr 3 (s) + AgNO 3 (aq) AgBr(s) + Fe(NO 3 ) 3 (aq) 34. What is the mass of iron(iii) bromide (295.55 g/mol) that yields 0.188 g ofsilver bromide (187.77 g/mol) precipitate? 0.0986 g 0.148 g 0.296 g 0.592 g 0.888 g FeBr 3 (s) + AgNO 3 (aq) AgBr(s) + Fe(NO 3 ) 3 (aq) 35. What is the mass of lead(ii) iodide (461.0 g/mol) precipitated from 0.830 g of potassium iodide (166.00 g/mol)? 0.149 g 0.598 g 1.15 g 2.31 g 4.61 g Pb(NO 3 ) 2 (aq) + KI(s) PbI 2 (s) + KNO 3 (aq) Page VII-9-9 / Limiting Reactant Worksheet II
36. What is the mass of potassium iodide (166.00 g/mol) that yields 0.500 g oflead(ii) iodide (461.0 g/mol) precipitate? 0.0900 g 0.180 g 0.360 g 0.694 g 2.78 g Pb(NO 3 ) 2 (aq) + KI(s) PbI 2 (s) + KNO 3 (aq) 37. What is the mass of insoluble calcium phosphate (310.18 g/mol) produced from 0.555 g of calcium chloride (110.98 g/mol)? 0.0662 g 0.517 g 0.596 g 1.55 g 4.65 g CaCl 2 (s) + Na 3 PO 4 (aq) Ca 3 (PO 4 ) 2 (s) + NaCl(aq) 38. What is the mass of sodium phosphate (163.94 g/mol) that yields 1.00 g of calcium phosphate (310.18 g/mol) precipitate? 0.264 g 0.358 g 0.931 g 1.06 g 8.38 g CaCl 2 (s) + Na 3 PO 4 (aq) Ca 3 (PO 4 ) 2 (s) + NaCl(aq) 39. What is the mass of aluminum oxide (101.96 g/mol) produced from 3.59 g of iron(ii) oxide (71.85 g/mol)? FeO(l) + Al(l) Fe(l) + Al 2 O 3 (l) 0.842 g 1.70 g 5.10 g 7.58 g 15.3 g Page VII-9-10 / Limiting Reactant Worksheet II
40. What is the mass of aluminum metal that reacts to give 1.00 g of iron? 0.322 g 0.483 g 0.725 g 0.966 g 1.449 g FeO(l) + Al(l) Fe(l) + Al 2 O 3 (l) 41. What is the mass of aluminum oxide (101.96 g/mol) produced from 1.74 g of manganese(iv) oxide (86.94 g/mol)? MnO 2 (l) + Al(l) Mn(l) + Al 2 O 3 (l) 0.988 g 1.36 g 2.04 g 2.22 g 3.06 g 42. What is the mass of aluminum metal that reacts to give 11.1 g of manganese metal? MnO 2 (l) + Al(l) Mn(l) + Al 2 O 3 (l) 3.64 g 4.09 g 5.45 g 7.27 g 8.18 g 43. What is the mass of hydrogen gas released from 2.70 g of aluminum metal and hydrochloric acid? 0.101 g 0.135 g 0.202 g 0.303 g 0.606 g Al(s) + HCl(aq) AlCl 3 (aq) + H 2 (g) Page VII-9-11 / Limiting Reactant Worksheet II
44. What is the mass of aluminum metal that reacts to give 1.00 g of hydrogen gas? Al(s) + HCl(aq) AlCl 3 (aq) + H 2 (g) 4.46 g 8.90 g 13.4 g 20.0 g 26.7 g Limiting Reactant Problems) 45. Considering the limiting reactant concept, how many moles of C are producedfrom the reaction of A and B? A(g) + 2 B(g) 3 C(g) 1.50 mol 3.00 mol 46. Considering the limiting reactant concept, how many moles of C are producedfrom the reaction of 1.50 mol A and 3.50 mol B? A(g) + 2 B(g) 3 C(g) 1.50 mol 3.50 mol 4.50 mol 5.25 mol 47. Considering the limiting reactant concept, how many moles of C are producedfrom the reaction of A and 4.50 mol B? A(g) + 3 B(g) 2 C(g) 3.00 mol 4.00 mol 4.50 mol Page VII-9-12 / Limiting Reactant Worksheet II
48. Considering the limiting reactant concept, how many moles of copper(i) sulfideare produced from the reaction of of copper and of sulfur? 2 Cu(s) + S(s) Cu 2 S(s) 1.50 mol 49. Considering the limiting reactant concept, how many moles of copper(i) sulfideare produced from the reaction of 3.00 mol of copper and of sulfur? 2 Cu(s) + S(s) Cu 2 S(s) 1.50 mol 4.00 mol 6.00 mol 50. Considering the limiting reactant concept, how many moles of cobalt(iii) oxideare produced from the reaction of of cobalt and of oxygengas? 4 Co(s) + 3 O 2 (g) 2 Co 2 O 3 (s) 0.667 mol 1.50 mol 51. Considering the limiting reactant, what is the mass of zinc sulfide (97.46 g/mol) produced from 0.750 g of zinc and 0.750 g of sulfur? Zn(s) + S(s) ZnS(s) 0.560 g 1.12 g 1.50 g 2.24 g 2.28 g Page VII-9-13 / Limiting Reactant Worksheet II
52. Considering the limiting reactant, what is the mass of zinc sulfide (97.46 g/mol) produced from 0.750 g of zinc and 0.350 g of sulfur? Zn(s) + S(s) ZnS(s) 0.530 g 1.06 g 1.10 g 1.12 g 2.28 g 53. Considering the limiting reactant, what mass of cobalt(iii) sulfide (214.07 g/mol)is produced from 0.750 g of cobalt and 0.350 g of sulfur? 2 Co(s) + 3 S(s) Co 2 S 3 (s) 0.779 g 1.36 g 2.34 g 2.72 g 5.45 g 54. Considering the limiting reactant, what is the mass of iron produced from 75.0 gof ferrous oxide (71.85 g/mol) and 25.0 g of magnesium metal? FeO(s) + Mg(s) Fe(l) + MgO(s) 28.7 g 29.1 g 57.4 g 58.3 g 100.0 g 55. Considering the limiting reactant, what is the mass of iron produced from 80.0 gof ferrous oxide (71.85 g/mol) and 20.0 g of magnesium metal? FeO(s) + Mg(s) Fe(l) + MgO(s) 23.0 g 31.1 g 45.9 g 62.2 g 100.0 g Page VII-9-14 / Limiting Reactant Worksheet II
56. Considering the limiting reactant, what is the mass of manganese produced from 25.0 g of manganese(iv) oxide (86.94 g/mol) and 25.0 g of aluminum metal? 15.8 g 38.2 g 47.4 g 50.9 g 67.8 g 3 MnO 2 (s) + 4 Al(s) 3 Mn(l) + 2 Al 2 O 3 (s) 57. Considering the limiting reactant, what is the volume of NO gas producedfrom 30.0 L of nitrogen gas and 40.0 L of oxygen gas? (Assume constant conditions.) N 2 (g) + O 2 (g) 2 NO(g) 30.0 L 40.0 L 60.0 L 80.0 L 58. Considering the limiting reactant, what is the volume of NO gas producedfrom 30.0 L of nitrogen gas and 20.0 L of oxygen gas? (Assume constant conditions.) N 2 (g) + O 2 (g) 2 NO(g) 20.0 L 30.0 L 40.0 L 60.0 L 59. Considering the limiting reactant, what is the volume of NO 2 gas produced from 3.00 L of NO gas and 2.00 L of oxygen gas? (Assume constant conditions.) 2 NO(g) + O 2 (g) 2 NO 2 (g) 1.00 L 2.00 L 3.00 L 4.00 L Page VII-9-15 / Limiting Reactant Worksheet II
60. Considering the limiting reactant, what is the volume of NO gas producedfrom 40.0 L of ammonia gas and 40.0 L of oxygen gas? (Assume constant conditions.) 4 NH 3 (g) + 5 O 2 (g) 4 NO(g) + 6 H 2 O(g) 32.0 L 40.0 L 50.0 L 80.0 L 61. Considering the limiting reactant, what is the volume of NO gas producedfrom 50.0 L of ammonia gas and 60.0 L of oxygen gas? (Assume constant conditions.) 4 NH 3 (g) + 5 O 2 (g) 4 NO(g) + 6 H 2 O(g) 48.0 L 50.0 L 60.0 L 75.0 L 62. Considering the limiting reactant, what is the volume of NO gas producedfrom 60.0 L of ammonia gas and 50.0 L of oxygen gas? (Assume constant conditions.) 4 NH 3 (g) + 5 O 2 (g) 4 NO(g) + 6 H 2 O(g) 40.0 L 50.0 L 60.0 L 62.5 L Page VII-9-16 / Limiting Reactant Worksheet II
Percent Yield 63. Starting with 1.550 g of potassium chlorate, a student releases 0.617 g of oxygen gas. If the calculated mass of oxygen gas is 0.607 g, what is the percent yield? 39.2% 39.8% 98.4% 102% 255% 64. Starting with 0.657 g of lead(ii) nitrate, a student collects 0.925 g of precipitate. If the calculated mass of precipitate is 0.914 g, what is the percent yield? 71.0% 71.9% 98.8% 101% 139% 65. Starting with 1.56 g of salicylic acid, a student prepares 1.75 g of aspirin. Ifthe calculated mass of aspirin is 1.88 g, what is the percent yield? 83.0% 89.1% 93.1% 107% 121% 66. The decomposition of 1.500 g of baking soda gave 0.200 L of carbon dioxide gas. If the calculated volume of carbon dioxide gas is 0.210 L, what is the percent yield? 63.5% 70.0% 95.2% 105% 158% 67. The decomposition of 1.500 g of potassium chlorate evolved 405 ml of oxygen gas. If the calculated volume of oxygen gas is 411 ml, what is the percent yield? 65.7% 67.3% 98.5% 101% 148% Page VII-9-17 / Limiting Reactant Worksheet II
68. The decomposition of 1.500 g of sodium nitrate produced 195 ml of oxygen gas. If the calculated volume of oxygen gas is 198 ml, what is the percent yield? 65.7% 68.0% 98.5% 102% 152% Page VII-9-18 / Limiting Reactant Worksheet II
Answer Key 1. A 2. A 3. B 4. B 5. A 6. A 7. D 8. C 9. B 10. B 11. B 12. B 13. B 14. C 15. A 16. B 17. A 18. C 19. B 20. C 21. B 22. B 23. A 24. C 25. C 26. A 27. B 28. D 29. C 30. E 31. E 32. A 33. D 34. A 35. C 36. C 37. B 38. D 39. B 40. A 41. B 42. D 43. D 44. B 45. B 46. C 47. B 48. A 49. A 50. A 51. B 52. B 53. A 54. C 55. C 56. A 57. C 58. C 59. C 60. A 61. A 62. A Page VII-9-19 / Limiting Reactant Worksheet II