Lesson 27 answers.pdf

Answers Lecture Exercises Lesson 27 1. 2 C8H18(l) + 25 O2(g) ? 16 CO2(g) + 18 H2O(g) 2. Examples: 2 moles of octane react with 25 moles of oxygen to form 16 moles of carbon dioxide and 18 moles of water. Or: 2 octane molecules react with 25 oxygen molecules to form 16 carbon dioxide molecules and 18 water molecules. 3. 100 octane molecules react with 1250 oxygen molecules to form 800 carbon dioxide molecules and 900 water molecules. 4. 1 mole of octane molecules react with 12.5 moles of oxygen molecules to form 8 moles of carbon dioxide molecules and 9 moles of water molecules. 5. CH3CH2OH + 3 O2 ? 2 CO2 + 3 H2O 6. 2 molecules of CO2 7. 2 moles of CO2 8. 25 mol O2/16 mol CO2 25 mol O2/18 mol H2O 25 mol O2/2 mol C8H18 9. 1 mol CH3CH2OH/3 mol O2 1 mol CH3CH2OH/2 mol CO2 2 mol CO2/ 3 mol H2O 10. 1.356 mol O2 11. 2.034 mol O2 12. 4.068 mol O2 13. 0.452 mol CH3CH2OH 14. 24.44 g water 43.39 g oxygen 59.66 g carbon dioxide 65.09 g oxygen 62.47 g ethanol 130.18 g oxygen 24.41 g water 20.82 g ethanol 15. yes 16. Component Molar mass in g/mol C8H18 114.23 O2 32 CO2 44.01 H2O 18.02 17. For O2: 10.0 g C8H18 x (1 mol/114.23 g) x (25 mol O2/2 mol C8H18) x (32 g/1 mol) = 35.02 g O2 For CO2: 10.0 g C8H18 x (1 mol/114.23 g) x (16 mol CO2/2 mol C8H18) x (44.01 g/1 mol) = 30.82 g CO2 For H2O: 10.0 g C8H18 x (1 mol/114.23 g) x (18 mol H2O/2 mol C8H18) x (18.02 g/1 mol) = 14.20 g H2O 18. 2 C8H18(l) + 17 O2(g) ? 16 CO(g) + 18 H2O(g) MM (CO) = 28.01 g/mol For O2: 10.0 g C8H18 x (1 mol/114.23 g) x (17 mol O2/2 mol C8H18) x (32 g/1 mol) = 23.86 g O2 For CO: 10.0 g C8H18 x (1 mol/114.23 g) x (16 mol CO/2 mol C8H18) x (28.01 g/1 mol) = 19.62 g CO For H2O: 10.0 g C8H18 x (1 mol/114.23 g) x (18 mol H2O/2 mol C8H18) x (18.02 g/1 mol) = 14.20 g H2O 19. Total equation: 3 MgCl2(aq) + 2 Na3PO4(aq) ? 6 NaCl(aq) + Mg3(PO4)2(s) Net ionic equation: 3 Mg2+(aq) + 2 PO43-(aq) ? Mg3(PO4)2(s) Component Molar mass in g/mol MgCl2 95.21 Na3PO4 163.94 NaCl 58.44 Mg3(PO4)2 262.86 For MgCl2: 75.00 g Mg3(PO4)2 x (1 mol/262.86 g) x (3 mol MgCl2/1 mol Mg3(PO4)2) x (95.21 g/1 mol) = 81.5 g MgCl2 For Na3PO4: 75.00 g Mg3(PO4)2 x (1 mol/262.86 g) x (2 mol Na3PO4/1 mol Mg3(PO4)2) x (163.94 g/1 mol) = 93.55 g Na3PO4 20. 2 AuCl3+ 3 H2 ? 2 Au + 6 HCl Component Molar mass in g/mol AuCl3 303.32 H2 2.016 Au 196.97 HCl 36.46 For Au, starting with 1.00 g H2: 1.00 g H2 x (1 mol/2.016 g) x (2 mol Au/3 mol H2) x (196.97 g/1 mol) = 65.14 g Au For Au starting with 100.0 g AuCl3: 100.0 g AuCl3 x (1 mol/303.32 g) x (2 mol Au/2 mol AuCl3) x (196.97 g/1 mol) = 64.94 g Au ABLECKING Microsoft Word - Answers LE Lesson 27