Chapter 4. Page 162, Practice Problems. 1. Atom Reactant Side Product Side Na 8 8 O H 8 8 Cr 4 4. Page 159, Quick Check

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1 Chapter 4 Page 157, Quick Check 1. Color change (red to silver), evolution of gas (O 2) and increase in solid mass. 2. CaO (s) + H 2O (l) 2 Ca(OH) 2(s) 3. Carbonic Acid decomposes to carbon dioxide gas and water Page 159, Quick Check a. Incorrect formula created b. Correct c. Missing Coefficient d. Correct e. Correct Page 161, Practice Problems 1. Atom Reactant Side Product Side Na 8 8 O H 8 8 Cr Al (s) + 3H 2SO 4 (aq) Al 2(SO 4) 3 (aq) + H 2 (g) Mg 3N 2 (s) + 6 H 2O (l) 3Mg(OH) 2 (s) + 2 NH 3 (g) 4 NH 3 (g) + 5 O 2 (g) 6 H 2O (l) + 4 NO (g) Page 162, Practice Problems 1. 2 Fe (s) + 3 Cl (g) 2 FeCl 3 (aq) 2. 2 (NH 4) 3P (aq) + 3 Pb(BrO 3) 2 (aq) Pb 3P 2 (s)+ 6 NH 4BrO 3 (aq) 3. 3 Ca (s) + Ni 2(SO 4) 3 (aq) 3 CaSO 4 (aq) + 2 Ni (s) Page 164, 4.1 Review Questions 1. For example: Rusting colour change Burning Wood (heat released) 2. a. Law of Conservation of Mass b. Antoine Lavoisier 3. a. Solid carbon combines with oxygen gas to form carbon dioxide gas. b. Methane gas combusts in oxygen gas to produce carbon dioxide gas and water vapour. c. Chlorine gas reacts with solid potassium iodide to form solid iodine and potassium chloride solid. d. Hydrochloric acid neutralises solid sodium hydroxide to form sodium chloride solution and water. e. Solid potassium fluoride decomposes to form solid potassium and fluorine gas. 4. a. CdF NaBr CdBr NaF b. 2 Cr + 3 F 2 2 CrF 3 c. Ca + 2 H 2O Ca(OH) 2 + H 2 d. 2 Bi(NO 3) Na 2S Bi 2S NaNO 3 e. C 2H 5OH + 3 O 2 2 CO H 2O f. 16 V +5 S 8 8 V 2S 5 g. 2 LiNO Li 6 Li 2O + N 2 h. Ca 3(PO 4) H 2SO 4 3 CaSO H 3PO 4 i. 2 PH O 2 P 2O H 2O j. 3 Ba + 2 Ag 3PO 4 Ba 3(PO 4) Ag k. Ca(ClO 3) 2 CaCl O 2 l. C 12H 22O O 2 12 CO H 2O m. Ca 2C + 4 H 2O 2 Ca(OH) 2 + CH 4 n. 2 NH 4Br + BaO 2 NH 3 + BaBr 2 + H 2O o. 3 LiAlH BF 3 3 LiF + 3 AlF B 2H 6 5. a. 2 Ti (s) + 3 Se (s) Ti 2Se 3 (s)

2 b. 2 H 3PO 4 (aq) + 3 Ba(OH) 2 (s) Ba 3(PO 4) 2 (s) + 6 H 2O (l) c. 2 N 2 (g) + 6 PbO (s) 2 Pb 3N 2 (s) d. XeF 6 (s) + 3 H 2O (l) XeO 3 (s) + HF (aq) e. Al 4C 3 (s) + 12 H 2O (l) 3 CH 4(g) + 4 Al(OH) 3 (s) f. 6 CO 2 (g) + 6 H 2O (l) C 6H 12O 6 (s) + 6 O 2 (g) g. Mg 3N 2(s) + 6 H 2O(l) 2 NH 3(g) +3 Mg(OH) 2(s) h. 2 Cu(NO 3) H 2O (s) 2 CuO (s) + 4 NO 2 + O 2 (g) + 6 H 2O (l) 6. a. 3 Ag + 4 HNO 3 NO + 3 AgNO H 2O b. 2 Al + 2 NaOH + 6 H 2O 2 NaAl(OH) H 2 c. 10 HNO Zn 4 Zn(NO 3) H 2O + NH 4NO 3 d. 6 H 2O + 4 As + 3 HClO 3 4 H 3AsO HClO e. 3 H 2SO 4 + H 2O KMnO 4 2 MnSO O H 2O + K 2SO 4 Page 169, Quick Check 1. P 2O 5 (g) + 3 H 2O (l) 2 H 3PO 4 (aq) Synthesis 2. CH 4 (g) + 2 O 2 (g) CO 2 (g) + 2 H 2O 3. H 2CO 3 (aq) H 2O (l) + CO 2 (g) Decomposition Page 170, Practice Problems 1. 2 Fe 2O 3 (s) 4 Fe (s) + 3 O 2 (g) Decomposition 2. 2 C 3H 7OH (l) + 9 O 2 (g) 6 CO 2 (g) + 8 H 2O (l) 3. Ag 2O (s) + H 2O (l) 2AgOH (l) Synthesis 4. Pb(OH) 4 (s) PbO 2 + H 2O Decomposition Page 171, Quick Check 1. 3 Na (s) + AlCl 3 (aq) 3 NaCl (aq) + Al (s) 2. Cu (s) + KBr (aq) No Reaction 3. F 2 (g) + 2 LiI (aq) 2 LiF (aq) + I 2 (g) 4. Ca (s) + 2 HOH (l) Ca(OH) 2 (s) + H 2 (g) Page 173, Quick Check 1. 3 HCl (aq) + Fe(OH) 3 (s) FeCl 3 (aq) + 6 H 2O 2. Zn (s) + 2 AgClO 3 (aq) 2 Ag (s) + Zn(ClO 3) 2 Single 3. (NH 4) 2S (aq) + 2 CsOH (aq) Cs 2S (aq) + 2 NH 3 (aq) + 2 H 2O Double 4. 8 Cl 2 (g) + 8 Li 2S (aq) 16 LiCl (aq) + S 8 (s) Page 176, 4.2 Review Questions 1. a. CdF NaBr CdBr (s) + 2 NaF Double b. Na 2SO Cu Cu 2SO 4 2 Na Single c. 2 Cr + 3 F 2 2 CrF 3 Synthesis d. 2 Fe(OH) 3 Fe 2O 3 + H 2O Decomposition e. Ca + 2 H 2O Ca(OH) 2 + H 2 Single f. 2 Bi(NO 3) Na 2S Bi 2S 3 (s) + 6 NaNO 3 Double g. C 25H O 2 25 CO H 2O h. 2 Al + 3 H 2SO 4 Al 2(SO 4) H 2 Single i. 2 LiClO 3 2 LiCl + 3 O 2 Decomposition j. 2 K + 2 Cl 2 2 KCl Synthesis k. 2 Au + 3 H 2S Au 2S H 2 Single l. 16 Nb + 5 S 8 8 Nb 2S 5 Synthesis m. P 4O H 2O 4 H 3PO 4 Synthesis n. 2 HClO Cl 2O + H 2O - Decomposition o. H 3PO KOH K 3PO H 2O - p. 6 Rb + Sc 2(CrO 4) 3 3 Rb 2CrO Sc Single q. 2 V(OH) 5 V 2O H 2O Decomposition r. 2 Ba 3P 2 6 Ba + P 4 Synthesis s. K 2C 2O 4 + Ca(NO 3) 2 CaC 2O 4 (s) + 2 KNO 3 Double t. BaCO HCl BaCl 2 + CO 2 + H 2O Double 2. a. See above b. b, k c. a,f,s d. See above 3. a. 2 Rb + ZnF 2 2 RbF + Zn Single b. Sc 2O H 2O 2 Sc(OH) 3 Synthesis c. Pb(NO 3) NaCl PbCl NaNO 3 Double d. H 2CO 3 H 2O + CO 2 Decomposition e. GeO SO 2 Ge(SO 3) 2 Synthesis f. SrCO 3 + H 2S SrS (aq) + H 2O + CO 2 Double g. 2 C 2H O 2 4 CO H 2O h. 2 Cs + NiCl 2 2 CsCl + Ni Single i. Zr(OH) 4 ZrO 2 + H 2O Decomposition j. 3 Br InI 3 2InBr 3 + 3I 2 Single k. H 3PO Ba(OH) 2 Ba 3(PO 4) 2 (s) + 6 H 2O l. 2 AgNO 3 + Ca(CH 3COO) 2 2 AgCH 3COO (s) + Ca(NO 3) 2 Double m. C 3H 5OH + 4 O 2 3 CO H 2O n. N 2O 5 + H 2O 2 HNO 3 Synthesis o. 2 AlCl Na 2CO 3 Al 2(NO 3) 3 (s) + 6 NaCl Double

3 p. NH 4F + LiOH LiF + NH 3 +H 2O Double q. 2 HNO 3 + Sr(OH) 2 Sr(NO 3) H 2O - r. 8 F K 2S 16 KF + S 8 Single s. Mg(OH) 2 MgO + H 2O Decomposition t. 6 Na + N 2 2 Na 3N Synthesis 4. a. 3 Mg (s) + N 2 (g) Mg 3N 2 (s) Synthesis b. H3PO4 (aq) + Fe(OH)3 (s) FePO4 (s) + 3 H2O (l) c. 2 C 4H 10 (g) + 13 O 2 (g) 8 CO 2 (g) + 10 H 2O (g) d. Zn (s) + CuSO 4 (aq) ZnSO 4 (aq) + Cu (s) Single e. SO 2 (g) + H 2O (g) H 2SO 3 Synthesis f. CaCO3 (s) + 2 HNO3 (aq) Ca(NO3)2 (aq) + CO2 (g) + H 2O (l) Double g. 2 Ni(OH)3 (s) + 3 Cd (s) 3 Cd(OH)2 (s) + 2 Ni (s) Single replacement h. 2 Au(NO 3) 3 (aq) + 3 Na 2CO 3 (aq) Au 2(CO 3) (s) + 6 NaNO 3 (aq) Double i. K2CrO4 + 2 AgNO3 (aq) Ag2CrO4 (s) + 2 KNO3 (aq) - Double j. CH 3OH (l) + 3 O 2 (g) 2 CO 2 (g) + 4 H 2O (g) k. NaHCO 3 (aq) + HCl (aq) H 2O (l) + CO 2 (g) + NaCl (aq) l. Pb(NO3) (aq) + 2 NaI (aq) PbI2 (s) + 2 NaNO3 (aq) Double m. Fe 2O 3 (s) + 3 H 2O (l) 2 Fe (OH) 3 (s) Synthesis n. 3Ag 2 S (s) + 2 Al (s) Al 2 S 3 (s) + 6 Ag (s) Single o. Na 2 C 2 O 4 (aq) + Ba(NO 3 ) 2 (aq) 2 NaNO 3 (aq)+ BaC 2O 4 (s) Double p. Ba (s) + H 2SO 4 (aq) BaSO 4 (s) + H 2 (g) Single q. 2 H 3PO 4 (aq) P 2O 5 (g) + 3 H 2O (l) Decomposition Page 179, Quick Check 1. Decomposition 2. Synthesis Single Page 182, Practice Problems 1. +1, , , +7, , +6, , , , , +5, , , +1, +4, -2 Page 182, Quick Check 1. 2 Mg (0) (0) + O 2 2Mg (+2) O (-2) 2. See above 3. 2 Mg 2e each O 2 Page 183, Quick Check 1. a. 2 b. 2 c. Mg O 2 2. a. 2 b. 1 No (2 of the Cl ions are spectators) Page 184, Practice Problems 1. 0, 0, -4, +1 OA: Si RA: H , +3, -1, 0, +2, -1 OA: Al 3+ RA: Ca 3. +2, -2, +5, -2, +4, -2, 0 OA: I 2O 5 RA: CO 4. -3, +1, 0, 0 OA: NH 3 RA: NH , +1, -2, +2, -2, +1, 0 OA: H 2O RA: Mg Page 187, 4.3 Review Questions 1. a. +2 b. +2 c. 0 d. -1 e. +2 f. -1 g. +1 h a. 2 Ca + O 2 2 CaO (Electron transfer) b. CaO + H 2O Ca(OH) 2 (No electron transfer) c. CaO + H 2O Ca(OH) 2 + H 2 (Electron transfer) d. Ca(OH) HCl CaCl H 2O (No electron transfer) 3. a. Species that gets reduced. (O.N. ) (Causes another species to be oxidized) b. Species that get oxidized. (O.N. ) (Causes another species to be reduced) c. The greater the electronegativity, the stronger the oxidizing agent will be, and the weaker the reducing agent will be. 4. a. +5, -2, -2, 0 KClO 3 is oxidized and reduced. b. 0, +1, +2, 0 Mg is oxidized, and Ag + is reduced. c. 0, 0, +5, -2 P 4 is oxidized, and O 2 is reduced. d. -3, +5, +1 NH 4NO 3 is oxidized, and NH 4NO 3 is reduced. 5. a. Alkali metals (I A) lose e easily (Low EN) b. Halogens (VII A) or 17 gain e easily (High EN)

4 6. a. OA: O 2 RA: Pb No e : 2e b. OA: Br 2 RA: Pb No e : 4e c. OA: H + RA: Pb No e : 3e d. OA: O 2 RA: Al No e : 6 ⅔ e 7. a. SO 2 (g) + CaO (s) CaSO 3 Synthesis/Not redox b. 2 KNO 3 (s) 2 KNO 2 (s) + O 2 (g) Decomposition/Redox c. Sr(OH) 2 (aq) + 2 HNO 3 (aq) Sr(NO 3) 2 (aq) + 2 H 2O (l) /Not redox d. 2 Al(OH) 3 (s) Al 2O 3 (s) + 3 H 2O (l) Decomposition/Not redox e. Cl 2 (g) + 2 CsI (aq) 2 CsCl (aq) + I 2 (s) Single /Redox f. P 4O 10 (s) + 6 H 2O (l) 4 H 3PO 4 (aq) Synthesis/Not redox g. 2 Al (s) + 3 Br 2 (l) 2 AlBr 3 (s) Synthesis/Redox h. 3 Zn (s) + 2 NiCl 3 (aq) 3 ZnCl 2 (aq) + 2 Ni (s) Single /Redox 8. a. Ox: Sn Sn e Rd: Ag + + e Ag b. Ox: 2 Cl Cl e Rd: F e 2 F Page 190, Quick Check Reaction Reactants Products Dissolving potassium hydroxide of propane Melting ice of iron by aluminum Formation of calcium hydroxide Page 191, Quick Check Reaction Dissolving potassium hydroxide of propane Melting ice of iron by aluminum Formation of calcium hydroxide Page 193, Practice Problems Endothermic or Endothermic 1. a. 2 C 2H 6 (g) + 7 O 2 (g) 6 H 2O (l) + 4 CO 2 (g) b. 2 C 2H 6 (g) + 7 O 2 (g) 6 H 2O (l) + 4 CO 2 (g) ΔH= a. 2 NH 3 (g) N 2 (g) + 3 H 2 (g) b. 2 NH 3 (g) N 2 (g) + 3 H 2 (g) ΔH= a. H 2 (g) + Br 2 (g) 2 HBr (g) b. H 2 (g) + Br 2 (g) 2 HBr (g) ΔH= Page 195, 4.4 Review Questions 1. a. Endothermic b. c. d. Endothermic e. Endothermic f. 2. a. C 3H 8 (g) C 3H 8 (l) b. 2 Li (s) + CaCl 2 (aq) 2 LiCl (aq) +Ca (s) c. 4 B (s) + 6 H2O (g) B2H6 (g) + 3 O2 (g) d. P 4 (s) + 6 Cl 2 (g) 4 PCl e. 2 NH 3 (g) + 3 N 2O (g) 4 N 2 (g) + 3 H 2O (l) f. Fe 3O 4 (s) + CO (g) FeO (s) + CO 2 (g) 3. a. 2 C (s) + 4 H2 (g) + O2 (g) 2 CH3OH (l) ΔH= -402 b. Cu (s) + H2 (g) + O2 (g) Cu(OH)2 (s) ΔH= -450 c. Sb4O6 (s) + 6 C (s) 4 Sb (s) + 6 CO (g) ΔH= 778 d. 2 NO 2 (g) 2 NO (g) + O 2 (g) ΔH= 112 e. 2 PCl 3 (g) + O 2 (g) 2Cl 3PO (g) ΔH= -572 f. 2 F 2 (g) + O 2 (g) 2 OF 2 (g) ΔH= a. 802 b mol NO 2 c. Released (). d. ΔH decomposition of OF 2 = 44 OF 2 e. 450 Cu(OH) 2 5. ΔH= 150 Endothermic 6. ΔH= -50 Page 199, Practice Problems J J J Work on the system Page 200, Practice Problems kj/mol rxn kj/mol rxn L Page 203, Practice Problems kj/mol rxn kj/mol rxn kj/mol rxn Page 207, Practice Problems 1. a kj/molrxn

5 b kj/molrxn kj/molrxn Page 210, Practice Problems kj/mol rxn kj/mol rxn kj/mol rxn Page 211, 4.5 Review Questions 1. q Heat (+) System gains thermal energy w Work (+) Work done on the system ΔE Internal Energy (+) Energy gained by the system (-) System loses thermal energy (-) Done by the system (-) Energy leaving the system Page 217, Quick Check 1. Metals have a much lower specific heat compared to liquid water. 2. The iron would reach 100 C first due to its lower specific heat. 3. The iron would cool to room temperature faster due to its lower specific heat. Page 220, Practice Problems J g C kj Page 222, Practice Problems C g C 2. a. pathway dependent b. state function c. pathway dependent d. state function e. pathway dependent J J 5. a ml b. 308 J ; 308 J required 6. a. (+) w system is positive because w = -ΔnRT, and Δn<0 as gaseous molecules are becoming liquid. As the gas is being compressed, work is being done ON the system, thus w is (+). b. (-) q system is negative because the substance changes from a gaseous state to liquid state. This is an exothermic process than requires forming hydrogen bonds, thus q system or ΔH is negative. c. ΔE system is impossible to determine without numerical values of w and q because they oppose each other (one is positive, one is negative). 7. O 3 + O à 2 O 2 ΔH o = -394 kj/mol rxn 8. ΔH o = kj/mol rxn 9. ΔH f = kj/mol rxn Formation of CsF(s) kj/mol rxn kj/mol rxn kj/mol rxn kj/mol rxn kj/mol rxn 15. a kj/mol rxn b kj/mol rxn 16. a. 43 kj/mol rxn b. 37 kj/mol rxn kj/mol rxn Page 224, Practice Problems kj/mol rxn kj/mol rxn C Page 227, Practice Problems kJ/mol rxn kj/mol rxn 3. a kj/ C b kj/mol rxn c C Page 229, 4.6 Review Questions 1. a. Zinc, Copper, Iron, Aluminum b. Zinc, Iron, Copper, Aluminum, g 3. The aluminum jug is far colder. Firstly, aluminum has a lower specific heat than plastic so the aluminum jug will lose heat faster than the plastic jug. Furthermore and perhaps more importantly so, the plastic jug contains 1 kg of water and water has a remarkably high specific heat. For this reason, the water and plastic jug need to be cooled simultaneously and the water s high heat content results in a lower drop in temperature compared to the empty aluminum jug. 4. Phosphate bonds are high energy because of the amount of energy released when they form. This means they actually require high energy when they are broken. However, the reaction in which high energy phosphate bonds are broken is coupled or followed by a series of other reactions in which bonds are formed. During this series of reactions the net

6 overall result is a release or production of energy J g C J/g C (Beryllium) C 10. a kj/mol rxn b. i. The change in temperature would be 1.5 times as much because HCL is now limiting. ii. The amount of heat produced would be 1.5 times larger. iii. No changes as the quotient of q/mole remains constant C x 10 3 kj/ mol g 14. a kj/mol rxn b kj/ C 15. a kj/mol rxn b % Page 234, Practice Problem mol NH mol H 2 O mol Ca Page 236, Practice Problems g g or 11,000kg mol B 4. 1 mol H 2 ; 1 mole of gas= 22.4L Page 237, Quick Check L Page 239, Practice Problems L O L g Page 240, Quick Check mol/l g L Page 241, Practice Problems g L L Page 243, 4.7 Review Questions 1. a mol CuO b g c L 2. a. 580 L b g c g g kj ml g mol g g g L KJ g g g KJ g L (21 ml) ml L Page 247, Quick Check 1. O 2 2. O=O, excess O Page 248, Practice Problems g excess Zn g excess NHCO g excess Ca Page 249, Quick Check 1. a. 84% b. 87.5% % Page 251, Practice Problems g g % Page 252, Practice Problems % 2. 93% g

7 Page 255, 4.8 Review Questions 1. No Reactants may be impure; rxn may not go 100% to completion; one reactant may be in excess 2. Excess obtained 3. expected 100% 4. Rarely. Need to apply % purity (make product mass smaller) % L 7. Limiting, 3.56 g Excess, 24.9 g mol 9. Excess, 12.5 g Limiting, 8.34 g % L g % L g % % %