Consider five solutions, each of which has the same mass of solute in 100.0 mL of solution. Which has the highest concentration as measured in molarity? a) KCl b) NaCl c) Na2SO4 d) NaF e) CaCl2 Lead (II) nitrate reacts with sodium chloride in aqueous solution to form a precipitate. What is the net ionic equation for this reaction? a) Pb2+ (aq) + 2 NO3– (aq) Pb(NO3)2 (s) b) Na2+ (aq) + Cl– (aq) NaCl (s) c) Pb2+ (aq) + 2 Cl– (aq) PbCl2 (s) d) Na+ (aq) + NO3– (aq) NaNO3 (s) Aqueous solutions of sodium sulfide and copper (II) chloride are mixed together. Which statement is correct? a) Both NaCl and CuS will precipitate from solution. b) No precipitate will form. c) Only CuS will precipitate from solution. d) Only NaCl will precipitate from solution. An aqueous solution of barium nitrate reacts with an aqueous solution of sodium sulfate. Identify the solid and indicate its coefficient in the balanced equation. a) NaNO3; 1 b) BaSO4; 1 c) NaNO3; 2 d) BaSO4; 2 e) None of these. Which of the following are oxidation–reduction reactions? i. PCl3 + Cl2 PCl5 ii. Cu + 2 AgNO3 Cu(NO3)2 + 2 Ag iii. CO2 + 2 LiOH Li2CO3 + H2O iv. FeCl2 + 2 NaOH Fe(OH)2 + 2 NaCl a) i. b) i. and ii. c) ii. and iii. d) iv. e) i., ii., and iii. What are the oxidation numbers of carbon in CO32-? a) +2 b) +4 c) –4 d) –3 e) -2 What are the oxidation numbers of carbon in CO2? a) +2 b) +6 c) –4 d) –2 e) +4 Which of the following compounds contains nitrogen with the highest oxidation number? a) NH3 b) NO2 c) NCl3 d) N2 e) NO How many grams of NaCl are contained in 350. mL of a 0.334 M solution of sodium chloride? a) 19.5 g b) 6.83 g c) 13.66 g d) 116.9 g e) 0.117 g What mass of calcium chloride, CaCl2, is needed to prepare 3.650 L of a 1.75 M solution? a) 231 g b) 6.39 g c) 53.2 g d) 111 g e) 709 g A 30.1-g sample of strontium chloride is dissolved in 112.5 mL of solution. Calculate the molarity of this solution. a) 21.4 M b) 1.69 M c) 42.4 M d) 0.268 M e) 2.17 M Consider an aqueous solution of calcium nitrate added to an aqueous solution of sodium phosphate. What is the formula of the solid formed in the reaction? a) Ca(PO4)2 b) CaPO4 c) Ca3(PO4)2 d) Ca3(PO3)2 e) C3PO4 For the reaction 4 FeCl2 (aq) + 3 O2 (g) 2 Fe2O3 (s) + 4 Cl2 (g), what volume of a 0.890 M solution of FeCl2 is required to react completely with 0.0144 moles of O2? a) b) c) d) e) 4.49 × 103 mL 17.2 mL 12.2 mL 21.6 mL 9.65 mL What mass of NaOH is required to react exactly with 25.0 mL of 3.0 M H2SO4? a) 3.0 g b) 0.7 g c) 6.0 g d) 150 g e) 0.075 g The oxidation state of iodine in IO3– is: a) 0 b) +3 c) –3 d) +5 e) –5 In the reaction 2 Cs (s) + Cl2 (g) 2 CsCl (s), Cl2 is a) the reducing agent b) the oxidizing agent c) oxidized d) the electron donor e) two of these A substance that, when dissolved in water, produces a solution that conducts electric current very efficiently is called a) a strong electrolyte b) a weak electrolyte c) a strong ion d) an electrical solute e) none of these The reaction 2 K (s) + Br2 (l) 2 KBr (s) is a(n) ______________ reaction. a) b) c) d) e) precipitation acid-base oxidation-reduction double-displacement single-replacement The reaction AgNO3 (aq) + NaCl (aq) AgCl (s) + NaNO3 (aq) is a(n) __________ reaction. a) precipitation b) acid-base c) oxidation-reduction d) single-replacement e) synthesis You have 100.0 mL of a 1.00 M solution of NaCl sitting in a beaker. After several days you test the solution and find that it has a concentration of 1.33 M. How much water must have evaporated? a) 20.0 mL b) 25.0 mL c) 75.0 mL d) 80.0 mL e) 13.3 mL You have 135.8 mL of a 2.50 M solution of Na2CrO4 (aq). You also have 125 mL of a 2.50 M solution of AgNO3 (aq). Calculate the concentration of Na+ after the two solutions are mixed together. a) 0.01 M b) 1.30 M c) 2.60 M d) 5.00 M e) 0.679 M In the reaction Zn + H2SO4 ZnSO4 + H2, which, if any, element is oxidized? a) zinc b) hydrogen c) sulfur d) oxygen e) none of these The equation 2C2H6 + 7O2 4CO2 + 6H2O is an oxidation-reduction reaction. True or false, and why? a) True; the carbon is oxidized, and the oxygen is reduced. b) True; the carbon is reduced, and the oxygen is oxidized. c) True; the carbon is oxidized, and the hydrogen is reduced. d) True; the oxygen is reduced, and the hydrogen is oxidized. e) False A 57.17-g sample of Ba(OH)2 is dissolved in enough water to make 1.800 liters of solution. How many mL of this solution must be diluted with water in order to make 1.000 L of 0.100 M Ba(OH)2? a) 539 mL b) 185 mL c) 18.5 mL d) 3.34 mL e) 300 mL