Question

53. Which of the following is an acid-base reaction? Select the best answer.

   (A). C(s) + O2(g)  CO2(g)

   (B). 2HClO4(aq) + Ca(OH)2(aq) 2H2O(l) + Ca(ClO4)2(aq)

   (C). Fe(s) + 2AgNO3(aq)  2Ag(s) + Fe(NO3)2(aq)

   (D). MgSO4(aq) + Ba(NO3)2(aq)  Mg(NO3)2(aq) + BaSO4(s)

   (E). All of the above are acid base reactions.

54. Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of K2S and Fe(NO3)2 are mixed.

   (A). Fe2+(aq) + S2-(aq)  FeS(s)

   (B). Fe2+(aq) + S2-(aq) + 2K+(aq) + 2NO3-(aq)  FeS(s) + 2K+(aq) + 2NO3-(aq)

   (C). K+(aq) + NO3-(aq)  KNO3(s)

   (D). Fe2+(aq) + S2-(aq) + 2K+(aq) + 2NO3-(aq)  Fe2+(aq) + S2-(aq) + 2KNO3(s)

55. According to the following reaction, what mass of PbCl2 can form from 422 mL of 0.110M KCl solution? Assume that there is excess Pb(NO3)2.

2KCl(aq) + Pb(NO3)2(aq)  PbCl2(s) + 2KNO3(aq) (balanced ?)

   (A). 7.19 g

   (B). 3.59 g

   (C). 6.45 g

   (D). 5.94 g

   (E). 1.30 g

56. When 10.00 moles of H2(g) react with 5.000 moles of O2(g) to form 10.00 moles of H2O(l) at 25°C and a constant pressure of 1.00 atm. If 683.0 kJ of heat are released during this reaction, and PΔV is equal to -37.00 kJ, then

   (A). ΔH° = -683.0 kJ and ΔE° = -646.0 kJ.

   (B). ΔH° = -683.0 kJ and ΔE° = -720.0 kJ.

   (C). ΔH° = +683.0 kJ and ΔE° = +720.0 kJ.

   (D). ΔH° = +683.0 kJ and ΔE° = +646.0 kJ.

57. Determine the molarity of a solution formed by dissolving 97.7 g LiBr in enough water to yield 750.0 mL of solution.

   (A). 0.130 M

   (B). 0.768 M

   (C). 2.30 M

   (D). 1.50 M

   (E). 1.18 M

59. Which one of the following compounds is(/are) soluble in water? Select all that apply.

   (A). Ca3(PO4)2

   (B). HgS

   (C). Ni(NO3)2

   (D). MgCO3

Answer 1

53. Which of the following is an acid-base reaction? Select the best answer.

B

54. Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of K2S and Fe(NO3)2 are mixed.

B

55. According to the following reaction, what mass of PbCl2 can form from 422 mL of 0.110M KCl solution? Assume that there is excess Pb(NO3)2.

2KCl(aq) + Pb(NO3)2(aq)  PbCl2(s) + 2KNO3(aq) (balanced ?)

yes it balanced

we have 0.110M of KCl it is equal to 0.110M of K+ and 0.110M Cl-

M it is equual to mol/vol mol of Cl- are equal to M.V V= to 0.422L and M = to 0.110

M.V = to 0.04642mol of Cl-

a mol of PBCl2 = 2mol of Cl-

the mol of PbCl2 formed = mol of Cl-/2 = 0.04642mol/2= 0.02321mol of PbCl

m= mass

m = mol*molecular weight of PbCl molecular weight of PbCl = to 277.9g/mol

m = 277.9g/mol*0.02321mol of PbCl2 = 6.45g

C

56. When 10.00 moles of H2(g) react with 5.000 moles of O2(g) to form 10.00 moles of H2O(l) at 25°C and a constant pressure of 1.00 atm. If 683.0 kJ of heat are released during this reaction, and PΔV is equal to -37.00 kJ, then

D because H is - for release heat and PV its energy lossed

57. Determine the molarity of a solution formed by dissolving 97.7 g LiBr in enough water to yield 750.0 mL of solution.

the atomic weight of Li is 6.97g/mol and atomic weight of Br = 79.904g/mol = molecular weight of LiBr =86.874g/mol

the mol of LiBr are 97.7g/86.87g/mol = 1.12mol of LiBr and The M = mol/V where V is in liters

M = 1.12mol/0.750l = 1.49M of LiBr and are equatl to 1.49M of Br- and 1.49M of Li+

D

59. Which one of the following compounds is(/are) soluble in water? Select all that apply.

C,D, A if its may formed complex and B descomposes sulfate and sulfuric acid