Review Chemistry Chapter 4

CHAPTER 4 REACTIONS IN AQUEOUS SOLUTION MULTIPLE CHOICE QUESTIONS 4. 1Which of the following compounds is a strong electrolyte? E A. H2O B. O2 C. H2SO4 D. C6H12O6 (glucose) E. CH3COOH (acetic acid) Answer: C 4. 2Which of the following compounds is a strong electrolyte? E A. H2O B. N2 C. KOH D. C2H6O (ethanol) E. CH3COOH (acetic acid) Answer: C 4. 3Which of the following compounds is a weak electrolyte? E A. HCl B. CH3COOH (acetic acid) C. C6H12O6 (glucose) D. O2 E. NaCl Answer: B 4. 4Which of the following compounds is a weak electrolyte? E A. HCl B. NH3 C. C6H12O6 (glucose) D. N2 E. KCl
Answer: B 4. 5Which of the following compounds is a nonelectrolyte? E A. NaF B. HNO3 C. CH3COOH (acetic acid) D. NaOH E. C6H12O6 (glucose) Answer: E 4. 6Which of the following compounds is a nonelectrolyte? E A. NaOH B. HNO3 C. CH3COOH (acetic acid) D. KF E. C2H6O (ethanol) Answer: E 4. 7Identify the major ionic species present in an aqueous solution of NaNO3. M A. Na2+, NO3 – B. Na+, N3 – , O3 C. Na+, N3 -, O32 – D. Na+, N+, O2 – E. Na+, NO3 – Answer: E 4. 8Identify the major ionic species present in an aqueous solution of Ca(OH)2. E A. Ca2+, H+, O2 – B. Ca2+, OH2- C. Ca+, H-, O2 – D.
Ca2+, O2H22 – E. Ca2+, OH – Answer: E 4. 9The distinguishing characteristic of all electrolyte solutions is that they: E A. contain molecules B. conduct electricity C. react with other solutions D. always contain acids E. conduct heat Answer: B 4. 10According to the solubility rules, which one of the following compounds is insoluble Ein water? A. NaCl B. MgBr2 C. FeCl2 D. AgBr E. ZnCl2 Answer: D 4. 11According to the solubility rules, which one of the following compounds is insoluble Ein water? A. Na2SO4 B. BaSO4 C. CuSO4 D. MgSO4 E. Rb2SO4 Answer: B 4. 2According to the solubility rules, which one of the following compounds is insoluble Ein water? A. CaCO3 B. (NH4)2CO3 C. Na2CO3 D. K2CO3 E. KNO3 Answer: A 4. 13According to the solubility rules, which one of the following is soluble in water? E A. Hg2Cl2 B. Na2S C. Ag2CO3 D. Ag2S E. BaSO4 Answer: B 4. 14According to the solubility rules, which one of the following is soluble in water? E A. AgBr B. AgCl C. Ag2CO3 D. AgNO3 E. Ag2S Answer: D 4. 15According to the solubility rules, which one of the following is soluble in water? E A. (NH4)3PO4 B. Ca3(PO4)2 C. AlPO4 D.

Ag3PO4 E. Mg3(PO4)2 Answer: A 4. 16According to the solubility rules, which one of the following is soluble in water? E A. CaSO4 B. BaSO4 C. PbSO4 D. K2SO4 Answer: D 4. 17In accordance with the solubility rules, which of the following will occur when Msolutions containing about 0. 1 g of Pb(NO3)2(aq) and KI(aq) /100 mL are mixed? A. KNO3 will precipitate; Pb2+ and I- will be spectator ions. B. No precipitate will form. C. Pb(NO3)2 will precipitate; K+ and I- will be spectator ions. D. PbI2 will precipitate; K+ and NO3- will be spectator ions. E. Pb2+ and I- will be spectator ions, and PbI2 will precipitate.
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Answer: D 4. 18In accordance with the solubility rules, which of the following will occur when Msolutions of CuSO4(aq) and BaCl2(aq) are mixed? A. CuCl2 will precipitate; Ba2+ and SO42 – will be spectator ions. B. CuSO4 will precipitate; Ba2+ and Cl – will be spectator ions. C. BaSO4 will precipitate; Cu2+ and Cl- will be spectator ions. D. BaCl2 will precipitate; Cu2+ and SO42 – will be spectator ions. E. No precipitate will form. Answer: C 4. 19In accordance with the solubility rules, which of the following will occur when Msolutions of ZnSO4(aq) and MgCl2(aq) are mixed? A.
ZnCl2 will precipitate; Mg2+ and SO42 – will be spectator ions. B. ZnSO4 will precipitate; Mg2+ and Cl- will be spectator ions. C. MgSO4 will precipitate; Zn2+ and Cl- will be spectator ions. D. MgCl2 will precipitate; Zn2+ and SO42 – will be spectator ions. E. No precipitate will form. Answer: E 4. 20Which of the following is the correct net ionic equation for the reaction that occurs M when solutions of Pb(NO3)2 and NH4Cl are mixed? A. Pb(NO3)2(aq) + 2NH4Cl(aq) > NH4NO3(aq) + PbCl2(s) B. Pb2+(aq) + 2Cl-(aq) > PbCl2(s) C. Pb2+(aq) + 2NO3-(aq) + 2NH4+(aq) + 2Cl-(aq) > 2NH4+(aq) + 2NO3-(aq) + PbCl2(s) D.
NH4+(aq) + NO3-(aq) > 2NH4NO3 Answer: B 4. 21The common constituent in all acid solutions is: M A. H2 B. H+ C. OH- D. H2SO4 E. Cl- Answer: B 4. 22Identify the ions present in an aqueous solution of LiOH. E A. Li2+, O- , H- B. Li+, OH- C. LiO-, H+ D. Li+, O2 – , H+ E. Li – , OH+ Answer: B 4. 23Identify the major ions present in an aqueous solution of HNO3. E A. HN+, O2 – B. OH- , NO3- C. OH- , NO+ D. H+, N3-, O2 – E. H+, NO3- Answer: E 4. 24What choice gives the correct formula of the salt formed in the neutralization Ereaction of hydrochloric acid and calcium hydroxide? A. CaO B.
CaCl2 C. CaH2 D. CaCl E. CaClH Answer: B 4. 25What is the chemical formula of the salt produced by neutralization of Ehydrobromic acid with Mg(OH)2? A. MgBr B. Mg2Br3 C. Mg3Br2 D. Mg2Br E. MgBr2 Answer: E 4. 26What is the chemical formula of the salt produced by neutralization of nitric acid M with Ca(OH)2? A. CaNO3 B. Ca2(NO3)3 C. Ca3(NO3)2 D. Ca2NO3 E. Ca(NO3)2 Answer: E 4. 27What is the chemical formula of the salt produced by neutralization of sodium Mhydroxide with sulfuric acid? A. NaSO3 B. Na2(SO4)3 C. Na(SO4)2 D. Na2SO4 E. Na3SO4 Answer: D 4. 8What is the chemical formula of the salt produced by neutralization of potassium M hydroxide (KOH) with sulfuric acid (H2SO4)? A. KSO3 B. K2(SO4)3 C. K2SO4 D. K(SO4)2 E. KSO4 Answer: C 4. 29The oxidation number of N in NaNO3 is: M A. +6 B. +5 C. +3 D. – 3 E. none of these Answer: B 4. 30The oxidation number of S in K2SO4 is: M A. +6 B. +4 C. +2 D. – 1 E. none of these Answer: A 4. 31The oxidation number of Mn in KMnO4 is: M A. +8 B. +7 C. +5 D. – 7 E. – 8 Answer: B 4. 32The oxidation number of Fe in K3Fe(CN)6 is: H A. +3 B. +2 C. +1 D. – 3 E. – 4 Answer: A 4. 3The oxidation number of Cr in Cr2O72 – is: H A. – 12 B. – 7 C. – 2 D. +6 E. +7 Answer: D 4. 34The oxidation number of Cl in ClO3- is: H A. – 1 B. +7 C. +5 D. +3 E. none of these Answer: C 4. 35The oxidation number of Cl in ClO4- is: H A. – 1 B. +1 C. +3 D. +5 E. none of these Answer: E 4. 36The maximum oxidation number of nitrogen is: H A. +8 B. +5 C. +3 D. +1 E. – 3 Answer: B 4. 37The highest possible oxidation number of carbon is: M A. +8 B. +6 C. +4 D. +2 E. – 4 Answer: C 4. 38Select the compound below in which sulfur has its highest possible oxidation number.
H A. H2S B. SO2 C. Na2SO4 D. H2SO3 E. SCl2 Answer: C 4. 39The oxidation number of N in N2H4 is: M A. +4 B. – 4 C. +2 D. – 2 E. 0 Answer: D 4. 40Which choice below gives the oxidation numbers for all three elements in Rb2SO3 Mcorrectly, and in the order shown in the formula? A. – 2, +6, – 2 B. – 1, +4, – 3 C. +2, +4, – 2 D. +1, +4, – 2 E. +1, +6, – 6 Answer: D 4. 41Which one of the following is a redox reaction? M A. H+(aq) + OH – (aq) > H2O(l) B. 2KBr(aq) + Pb(NO3)2(aq) > 2KNO3(aq) + PbBr2(s) C. CaBr2(aq) + H2SO4(aq) > CaSO4(s) + 2HBr(g) D. Al(s) + 3H2SO4(aq) > Al2(SO4)3(aq) + 3H2(g) E. CO32 – + HSO4- > HCO3- + SO42 – Answer: D 4. 42Which of the following reactions does not represent an oxidation- Mreduction reaction? A. 3Al + 6HCl > 3H2 + AlCl3 B. 2H2O > 2H2 + O2 C. 2NaCl + Pb(NO3)2 > PbCl2 + 3NaNO3 D. 2NaI + Br2 > 2NaBr + I2 Answer: C 4. 43In the following reaction the oxidizing agent is: H 5H2O2 + 2MnO4- + 6H+ > 2Mn2+ + 8H2O + 5O2 A. H2O2 B. MnO4- C. H+ D. Mn2+ E. O2 Answer: B 4. 44In the following reaction the oxidizing agent is: H 5S + 6KNO3 + 2CaCO3 > 3K2SO4 + 2CaSO4 + CO2 + 3N2 A. S B. N2 C. KNO3 D. CaSO4 E. CaCO3
Answer: C 4. 45Identify the oxidizing agent in the following reaction: H 2MnO4- + 5H2SO3 > 2Mn2+ + 5SO42 – + 4H+ + 3H2O A. MnO4- B. H2SO3 C. Mn2+ D. SO42 – E. H+ Answer: A 4. 46Identify the reducing agent in the following reaction: H 5Fe2+(aq) + MnO4-(aq) + 8H+(aq) > 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) A. Fe2+ B. MnO4- C. H+ D. Mn2+ E. Fe3+ Answer: A 4. 47Identify the reducing agent in the following reaction. M Cd + NiO2 + 2H2O > Cd(OH)2 + Ni(OH)2 A. Cd B. NiO2 C. H2O D. Cd(OH)2 E. Ni(OH)2 Answer: A 4. 48What element is oxidized in the following reaction? M 3Cu + 8HNO3 ? Cu(NO3)2 + 2NO + 4H2O A. Cu B. H C. N D. O E. H2O Answer: A 4. 49What element is oxidized in the following reaction? M Cd + NiO2 + 2H2O > Cd(OH)2 + Ni(OH)2 A. Cd B. Ni C. O D. H Answer: A 4. 50What element is oxidized in the following reaction? M H2SO4 + Cd(OH)2 > 2H2O + CdSO4 A. H B. S C. O D. Cd E. none of these Answer: E 4. 51What element is reduced in the following reaction? M Cu + 2H2SO4 > CuSO4 + SO2 + 2H2O A. Cu B. H C. S D. O E. H2O Answer: C 4. 52Predict the products of the following displacement reaction. M Fe(s) + CuSO4(aq) > A. CuS(s) + Fe2SO4(aq)
B. Fe(s) + Cu(s) + SO4(aq) C. Cu(s) + FeSO4(aq) D. FeCuSO4 E. FeO(s) + CuSO3(aq) Answer: C 4. 53Complete and balance the following half-reaction. M ClO- + e- > Cl- (basic solution) The balanced half-reaction will show which of the following: A. two hydroxide ions on the right side B. one electron on the left side C. six H+ ions on the right side D. six H+ ions on the left side E. two water molecules on the left side Answer: A 4. 54Complete and balance the following redox equation. When balanced with Mwhole number coefficients, the coefficient of S is: H2S + HNO3 > S + NO (acidic solution) A. 1 B. 2 C. 3 D. E. 6 Answer: C 4. 55When balanced, what is the coefficient of Sn in the equation? M Sn + HNO3 > SnO2 + NO2 + H2O (acidic solution) A. 1 B. 2 C. 3 D. 4 E. 5 Answer: A 4. 56Complete and balance the following redox reaction. What is the coefficient of H2O M when the equation is balanced with the smallest whole number coefficients? MnO4- + SO32 – > Mn2+ + SO42 – (acidic solution) A. 3 B. 4 C. 5 D. 8 E. none of these Answer: A 4. 57Complete and balance the following redox reaction. What is the coefficient of H2S Mwhen the equation is balanced with the set of smallest whole numbers?
H2S + MnO4- > Mn2+ + SO42 – (acidic solution) A. 1 B. 2 C. 4 D. 5 E. none of these Answer: D 4. 58Complete and balance the following redox equation. What is the coefficient of H2O Mwhen the equation is balanced with the set of smallest whole numbers? MnO4- + I – > MnO2 + IO3- (basic solution) A. 1 B. 2 C. 4 D. 10 E. none of these Answer: A 4. 59Complete and balance the following redox reaction. What is the coefficient of OH- Mwhen the equation is balanced with the set of smallest whole numbers? MnO4- + I – > MnO2 + IO3- (basic solution) A. 1 B. 2 C. 4 D. 10 E. none of these
Answer: B 4. 60Complete and balance the following redox equation with the smallest set of whole- Mnumber coefficients. Now sum the coefficients of all species in the balanced equation. Remember the coefficients equal to one. The sum of the coefficients is: BrO3- (aq) + Sb3+(aq) > Br – (aq) + Sb5+(aq) (acidic solution) A. 4 B. 12 C. 13 D. 17 E. none of these Answer: D 4. 61Complete and balance the following redox reaction with the smallest set of whole-number coefficients. M When correctly balanced the sum of all the coefficients in the equation will be: (Recall, the absence of a coefficient is understood to be a 1)
PbO2(s) + Cl- > Pb2+ + Cl2(g) (acidic solution) A. 2 B. 4 C. 5 D. 9 E. 11 Answer: E 4. 62Complete and balance the following redox equation with the smallest set of whole Mnumber coefficients possible. What is the sum of the coefficients? (Remember the coefficients equal to one. ) HI + HNO3 > I2 + NO (acidic solution) A. 5 B. 7 C. 14 D. 17 E. none of these Answer: D 4. 63Complete and balance the following redox equation with the smallest set of whole-number coefficients Mpossible. What is the sum of the coefficients? MnO4- + Br – > Mn2+ + Br2 (acidic solution) A. 6 B. 17 C. 1 D. 29 E. 43 Answer: E Complete and balance the following redox equation with the smallest set of whole-number coefficients Mpossible. What is the sum of the coefficients? Bi(OH)3 + SnO2 2 – > Bi + SnO32 – (basic solution) A. 32 B. 25 C. 16 D. 13 E. none of these Answer: D 4. 65Complete and balance the following redox equation with the smallest set of whole-number coefficients Mpossible. What is the sum of the coefficients? Br2 > BrO3- + Br- (basic solution) A. 9 B. 12 C. 18 D. 21 E. none of these Answer: C 4. 66Which of the following is a displacement reaction? E A. NaN3(s) > 2Na(s) + 3N2(g) B. Fe2O3(s) + 2Al(s) > 2Fe(s) + Al2O3(s) C. 3NO2(g) + H2O(l) > 2HNO3(aq) + NO(g) D. 2P(s) + 3Cl2(g) > 2PCl3(g) E. 2ZnS(s) + 3O2(g) > 2ZnO(s) + 2SO2(g) Answer: B 4. 67Which of the following is a halogen displacement reaction? E A. 2KBr(aq) + Cl2(g) > 2KCl(aq) + Br2(l) B. 2Na(s) + 2H2O(l) > 2NaOH(aq) + H2(g) C. CaBr2(aq) + H2SO4(aq) > CaSO4(s) + 2HBr(g) D. 2KNO3(s) > 2KNO2(s) + O2(g) E. 2LiOH(aq) + H2SO4(aq) > Li2SO4(aq) + 2H2O(l) Answer: A 4. 68Which of the following is a precipitation reaction? M A. 2H2(g) + O2(g) > 2H2O(l) B. CaBr2(aq) + H2SO4(aq) > CaSO4(s) + 2HBr(g) C. KNO3(s) > 2KNO2(s) + O2(g) D. 2KBr(aq) + Cl2(g) > 2KCl(aq) + Br2(l) E. 2Al(s) + 3H2SO4(aq) > Al2(SO4)3(aq) + 3H2(g) Answer: B 4. 69Which of the following is an acid-base neutralization reaction? E A. 2Al(s) + 3H2SO4(aq) > Al2(SO4)3(aq) + 3H2(g) B. SO2(g) + H2O(l) > H2SO3(g) C. LiOH(aq) + HNO3(aq) > LiNO3(aq) + H2O(l) D. 2KBr(aq) + Cl2(g) > 2KCl(aq) + Br2(l) E. CaBr2(aq) + H2SO4(aq) > CaSO4(s) + 2HBr(g) Answer: C 4. 7025. 0 mL of a 0. 175 M solution of KOH is diluted with pure water to a final Mvolume of 750. 0 mL. What is the final molarity of the KOH solution? 0. 00583 M 0. 0163 M 0. 0333 M 0. 229 M
Answer: A 4. 71Consider the solution reaction AlCl3 + 3AgNO3 > 3AgCl + Al(NO3)3. M What volume of 0. 100 M AlCl3 will exactly react with 55. 0 mL of 0. 162 M AgNO3? 89. 1 mL 9. 90 mL 46. 2 mL 29. 7 mL Answer: D 4. 72What is the molarity of a solution in which 26. 0 grams of BaCl2 M(molar mass = 208. 2 g/mol) are dissolved in enough water to make 450. 0 mL of solution? 0. 278 M 0. 617 M 1. 00 M 3. 41 M Answer: A 4. 73If 40. 0 mL of H2SO4 solution reacts with 0. 212 g of Na2CO3, what is the Mmolarity of the H2SO4 solution? Na2CO3 + H2SO4 > Na2SO4 + CO2 + H2O 0. 50 M 0. 10 M 0. 20 M 0. 40 M 0. 050 M Answer: E 4. 4What volume of 0. 122 M HCl would react with 26. 2 mL of 0. 176 M NaOH? M 37. 8 mL 18. 2 mL 5. 56 mL 26. 3 mL 75. 6 mL Answer: A 4. 75 What is the oxidation number of N in NaNO3? M +1 +2 +3 +4 +5 Answer: E 4. 76In the following reaction, which species is being reduced? MFeBr3 + 3Cl2 > 2FeCl3 + 3Br2 A. the Cl in Cl2 B. the Fe in FeBr3 C. the Br in FeBr3 D. This is not a redox reaction. Answer: A 4. 77 Which is the oxidation number of arsenic in K3AsO4? M +2 +3 +4 +5 +6 Answer: D 4. 78In which of the compounds below is nitrogen in the +1 oxidation state? M A. N2O4 B. HNO3 C. N2 D. N2O E. none of these Answer: D . 79 Which reaction below is NOT an oxidation-reduction reaction? M CaCl2(aq) + Na2CO3(aq) > CaCO3(s) + 2 NaCl(aq) 2 Na(s) + 2 H2O(l) > 2 NaOH(aq) + H2(g) 2 H2(g) + O2(g) > 2 H2O(g) Zn(s) + Cu(NO3)2(aq) > Zn(NO3)2(aq) + Cu(s) Answer: A 4. 80 Identify the oxidizing agent in the following reaction: 2 Na(s) + H2(g) > 2 NaH(s) M Na(s) NaH(s) H2(g) Answer: C 4. 81Which of the following is the correct NET IONIC equation for the M neutralization of acetic acid (HAc) with Ca(OH)2? (Ac = acetate ion) 2 HAc + Ca(OH)2 > CaAc2 + 2 H2O H+ + OH – > H2O HAc + OH – > Ac – + H2O 2 H+ + Ca(OH)2 > Ca2+ + 2 H2O
Answer: C 4. 82 Which of the following is INCORRECTLY classified? (Ac = acetate ion) E HAc / weak electrolyte HCl / strong electrolyte NaCl / strong electrolyte NaOH / weak electrolyte H2O / nonelectrolyte Answer: D 4. 83Which of the following compounds are INCORRECTLY classified with respect to its solubility in water? M NaBr / soluble KCrO4 / insoluble MgCl2 / soluble AgCl / insoluble PbS / insoluble Answer: B 4. 84 Which of these is a weak acid? E HNO3 H2SO4 HBr HI H2S Answer: E 4. 85Solutions of BaCl2(aq), Na2SO4(aq) and KNO3(aq) are mixed together. MWhat compound is likely to precipitate from the solution?
NaNO3 Ba(NO3)2 BaSO4 KCl K2SO4 Answer: C SHORT ANSWER QUESTIONS 4. 86Define solution, solute and solvent. E Answer: A solution is a homogeneous mixture of two or more substances. The substance present in a smaller amount is called the solute, while the substance present in the larger amount is called the solvent. 4. 87Identify each of the following compounds as an electrolyte or nonelectrolyte. E a. NaOH___________________ b. H2SO4___________________ c. methanol___________________ d. C12H22O11 (sucrose)___________________ e. MgCl2___________________ Answer: a. electrolyte b. electrolyte c. onelectrolyte d. nonelectrolyte e. electrolyte 4. 88Identify each of the following compounds as a strong electrolyte, weak electrolyte, Eor non electrolyte. a. CH3OH (methanol)____________________ b. CH3COOH____________________ c. KNO3____________________ d. NH3____________________ e. NH4Cl____________________ Answer: a. nonelectrolyte b. weak electrolyte c. strong electrolyte d. weak electrolyte e. strong electrolyte 4. 89Describe three situations or conditions in which a reaction will proceed to Mcompletion. Answer: a. reactions in which a precipitate is formed b. reactions in which H2O is formed c. eactions in which a gas is formed 4. 90Define and illustrate with an example the difference between an electrolyte and Mnonelectrolyte. Answer: (answers will vary) An electrolyte is a substance that will dissolve in water and break up into ions so the solution can conduct electricity. An example is Sodium hydrogen carbonate. A nonelectrolyte is a substance that does not break up into ions when dissolved in water and the resulting solution does not conduct electricity. An example is sugar. 4. 91Define precipitate and illustrate with an example. E Answer: A precipitate is an insoluble solid that separates from a solution.
CoCl2 (aq) + Na2CO3(aq) > CoCO3 (s) + 2NaCl (aq) CoCO3 would be the precipitate in this reaction. 4. 92What are three characteristics of a base? E Answer: a. Bases taste bitter. b. Bases feel slippery. c. Bases change change red litmus paper to blue. 4. 93What are three characteristics of an acid? E Answer: a. Acids taste sour. b. Acids change blue litmus paper to red. c. Acids react with certain metals to produce hydrogen gas . 4. 94What kind of bonding is found in all salts? E Answer: ionic 4. 95Give an example of a monoprotic acid, diprotic acid, and triprotic acid. E Answer: (answers will vary) HNO3 , H2CO3 , H3PO4 . 96Write the net ionic equation for the following reaction. Aqueous iron (III) sulfate is E added to aqueous sodium sulfide to produce iron (III) sulfide solid and aqueous sodium sulfate. Answer: 2Fe3+ (aq) + 3S2 – (aq) > Fe2S3 (s) 4. 97What is the oxidation number for each of the elements in the following compound? M Cs2Cr2O7 Answer: Cs1+, Cr6+, O2 – 4. 98Identify the element being oxidized, the element being reduced, the oxidizing Magent, and the reducing agent in the following reactions. 4Al + 3O2 > 2Al2O3 Answer: Al is oxidized;O2 is reduced; Al is the reducing agent; O2 is the oxidizing agent . 99Identify the element being oxidized, the element being reduced, the oxidizing Magent, and the reducing agent in the following reactions. 2KBr + F2 ? > Br2 + 2KF Answer: Br – is oxidized, F2 is reduced, KBr is the reducing agent, F2 is the oxidizing agent 4. 100What is the oxidation number for each of the elements in the following compound? M BaNaPO4 Answer: Ba, +2; Na, +1; P, +5; O, -2 4. 101What is the oxidation number for each of the elements in the following compound? M K2TaF7 Answer: K, +1; Ta, +5; F, -1 4. 102Thorium metal is prepared by reacting thorium oxide with calcium. M ThO2 + 2Ca > Th + 2CaO
What substance is reduced? What is the reducing agent? What substance is oxidized? What is the oxidizing agent? Answer: Th4+ is reduced, Ca is the reducing agent, Ca is oxidized, ThO4 is the oxidizing agent 4. 103Batteries in our cars generate electricity by the following chemical reaction. M Pb + PbO2 + 2H2SO4 > 2PbSO4 + 2H2O What substance is reduced? What is the reducing agent? What substance is oxidized? What is the oxidizing agent? Answer: Pb4+ is reduced, Pb is the reducing agent, Pb is oxidized, PbO2 is the oxidizing agent 4. 104Describe the procedure used to make 3. 0 liters of a 2. M KCl solution, starting Hwith solid KCl. Answer: a. Determine the molar mass of KCl, which is 74. 55 g/mol. b. Weigh out 447. 3 g of KCl and dissolve to form exactly 3 liters of solution. 4. 105What is the molarity of a solution that contains 5. 0 moles of solute in 2. 00 liters of Esolution? Answer: 2. 5 M 4. 106The solubility of Ba(NO3)2 is 130. 5 g per liter at 0°C. How many moles of Hdissolved salt are present in 4. 0 L of a saturated solution of a Ba(NO3)2 containing 130. 5 g/L at 0°C? Answer: 2. 0 mol 4. 107What is the molar concentration of ions in a solution prepared by mixing M100 mL of 2. 0M KCl with 50 mL of a 1. M CaCl2 solution? Answer: 4. 2 M 4. 108What volume of concentrated nitric acid (15. 0 M) is required to make 100 mL of a M3. 0 M nitric acid solution? Answer: 20 mL 4. 109During a titration the following data were collected. A 10 mL portion of an Munknown solution was titrated with 1. 0 M NaOH. It required 40 mL of the base to neutralize the sample. (a) What is the molarity of the acid? (b) How many moles of acid are present in 2. 0 liters of this unknown solution? Answer: a. 4 M b. 8 mol 4. 110If 145 g of potassium nitrate were added to water to make 1500 mL of solution, Mwhat would be the molarity of the resulting solution?
Answer: . 956 M 4. 111During a titration the following data were collected. A 50 mL portion of an HCl Msolution was titrated with 0. 50 M NaOH. It required 200 mL of the base to neutralize the sample. How many grams of acid are present in 500 mL of this acid solution? Answer: The acid is 2 M. 36. 5 g of HCl 4. 112Identify the Bronsted/Lowry acid in the following reaction. M NH3 + H2O > NH4+ + OH- Answer: H2O 4. 113Identify each of the following as either good or poor conductors of electricity. M a. CaSO4 b. Pb(C2H3O2)2 c. glacial acetic acid d. gasoline (C8H18)
Answer: a. good b. good c. poor d. poor 4. 114What is the substance acting as a Bronsted-Lowry acid in the following reaction. M HSO4- + NH4+ > H2SO4 + NH3 Answer: NH4+ 4. 115The water solution found in cells and in blood makes up approximately 80% of the mass of the human body. This solution has a concentration of 0. 21 M NaCl and has a density of 1 g/mL. How many pounds of salt are present in an 180 lb adult? Answer: 1. 77 lbs (802. 5 g) TRUE-FALSE QUESTIONS 4. 116We balance chemical equations because they obey the law of definite proportions. M Answer: F 4. 17From the following equation, we can deduce that six hundred P4O10 molecules M would react with one hundred H2O molecules. P4O10(s) + 6H2O(l) > 4H3PO4(aq) Answer: F 4. 118The following equation is balanced. M Ca(NO3)2(aq) + H2SO4(aq) > CaSO4(s) + 2HNO3(g) Answer: T 4. 119Sugar dissolves in water, therefore it is a strong electrolyte. E Answer: F 4. 120Silver chloride (AgCl) has an extremely low solubility in water; therefore, it is a Eweak electrolyte. Answer: F 4. 121Most compounds containing chlorides, bromides, and iodides are soluble except Ethose of Ag+, Hg, and Pb2+.
Answer: T 4. 122The following reaction is an acid-base neutralization reaction. E H2SO4(aq) + CaBr2(aq) > CaSO4(s) + 2HBr(g) Answer: F 4. 123The oxidation number of N in NO is +7. E Answer: F 4. 124Hydrogen is oxidized in the following reaction. M H2 + Cl2 > 2HCl Answer: T 4. 125The following equation is an example of a net ionic equation. M Na+ + Br- + Ag+ + NO3- > AgBr(s) + Na+ + NO3- Answer: F 4. 126The oxidation number of iodine increases by 6 in the following reaction. M 2MnO4- + I – + H2O > 2MnO2 + IO3- + 2OH- Answer: T