992_3rd_Exam_1000518
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1)For the reaction: Mg(s) + 2 AgNO3(aq) 2 Ag(s) + Mg(NO3)2(aq) Write a voltaic diagram for the reaction.
A) Mg(s) Mg2+ Ag (aq) Ag (s) B) Ag(s) Mg2+ (aq) Ag (aq) Mg(s) C) Mg(s) Mg2+ Ag(s) Ag (aq) D) Ag(aq) Ag(s) Mg(s) Mg2+ (aq)
E) Ag(s) | Ag(aq) Mg2+(aq) | Mg(s) Answer: A
Table 20.1 Selected Standard Electrode Potentials at 25°C
Reaction E°, V
Mg2+ (aq) + 2 e- Mg (s) -2.356
Fe2+ (aq) + 2 e- Fe (s) -0.440
Pb2+ (aq) + 2 e- Pb (s) -0.125
2 H (aq) + 2 e- H2 (g) 0.0
Cu2+ (aq) + 2 e- Cu (s) +0.337
I2 (s) + 2 e- 2 I (s) +0.535
Fe3+ (aq) + 2 e- Fe2+ (aq) +0.771
Ag (aq) + e- Ag (s) +0.800
O2 (g) + 4 H (aq) + 2 e- 2 H2O +1.229
Cl2 (g) + 2 e- 2 Cl (aq) +1.358
F2 (g) + 2 e- 2 F (aq) +2.866
2) (Refer to Table 20.1) Which of the following will oxidize Pb to Pb2+ but not Fe2+ to Fe3+?
A) Ag+ B) Cu2+ C) Mg2+ D)O2 E)Cl2
Answer: B
3)(Refer to Table 20.1) Calculate the value of G° for the following reaction, in kJ.
Cl2 (g) + 2 F- (aq) 2 Cl- (aq) + F2 (g)
A) -291 B) +291 C) -145 D) 150 E) +145
Answer: B
4) List the following in order of increasing atomic radius: V, Sc, Fe, Ti A) Fe < Sc < Ti < V
B) V < Fe < Sc < Ti C) Sc < Ti < V < Fe D) Ti < V < Fe < Sc E) Fe < V < Ti < Sc Answer: E
5) Give the correct name for [Fe(H2O)4(OH)2] . A) diaquotetrahydroxoiron(III)
B) tetrahydroxodiaquoferrate(III) C) hydrated iron hydroxide D) tetraaquadihydroxoiron(III)
E) tetrawaterdihydroxoiron(III) Answer: D
6) What is the cell diagram for the spontaneous cell involving the Cl2 Cl (1.358 V) and the Sn2+ Sn (-0.137V) half cells in STP condition?
A) Pt Cl2(g) Cl (aq) Sn2+(aq) Sn(s) B) Sn(s) Cl (aq) Sn2+(aq) Sn(s) C) Sn(s) Sn2+(aq) Cl (aq) Cl2(g) Pt D) Sn(s) Sn2+(aq) Cl (aq) Cl2(g)
E) Cl2(g) Cl (aq) Sn2+(aq) Sn(s) Answer: C
7) Write the probable electron configuration for Ti2+.
A) [Ar]3d2 B) [Ar]5s2 C) [Ar]4s24d4 D) [Ar]4s13d5 E) [Ar]4s2
Answer: A
8) Which of the following has the largest molar entropy?
A)H2(g) B)I2(g) C)He(g) D)Xe(g)
Answer: B
9) Determine Ecell at 25°C for the following reaction at 25°C:
Al Al3+(0.435 M) Sn2+(2.12 × 10-3 M) Sn 3 Sn2+ + 2 Al(s) 2 Al3+ + 3 Sn(s)
Al3+ + 3 e- Al(s) E° = -1.676 V Sn2+ + 2 e- Sn(s) E° = -0.137 V
A) 1.227 V B) 1.611 V C) 1.487 V D) 1.467 V E) 1.562 V
Answer: D
10)The two different compounds [Cu(NH3)4][Fe(CN)4(H2O)2] and [Cu(CN)4]Fe(NH3)4(H2O)2] are examples of ________.
A) coordination isomers B) linkage isomers C) geometric isomers D) ionization isomers
E) optical isomers Answer: A
11) Which of the following ions is highest in the spectrochemical series: NO2 , NH3, Br , ox2-, H2O
A) ox2- B)H2O C)NH3 D) Br E) NO2
Answer: E
12) Choose the INCORRECT statement.
A) Primary batteries' cell reactions cannot be reversed.
B) Cells can be joined in series to increase the total voltage.
C) A concentration cell consists of half cells with identical electrodes but different ion concentrations.
D) A primary battery is recharged by passing electricity through the battery.
E) Secondary batteries' cell reaction can be reversed.
Answer: D
13) One mole of electrons has a charge of:
A) 96,485 C B) 6.02 × 1023 A C) 1.60 × 10-19 D) 96,485 A
E) 96,485 F Answer: A
14)A solution of AgNO3 is electrolyzed by passing 144 A of current for 102 min. What mass of silver plates out?
A) 5.91 × 104 g B) 16.4 g C) 6.84 g D) 9.13 g E) 985 g
Answer: E
15) Write the equation for treatment of Ag with CN-.
A) 4 Ag(s) + 8 CN + O2(g) + 2 H2O(l) 4 [AgCN] + 4 CO(g) + 4 NH B) 4 Ag(s) + 8 CN + O2(g) + 2 H2O(l) 4 [Ag(CN)2] + 4 OH C) 4 Ag(s) + 2 CN + O2(g) + 2 H2O(l) 4 AgO(s) + 4 CO(g) + 4 NH D) 4 Ag(s) + 8 CN + O2(g) + 2 H2O(l) 4 AgO(s) + 2 H2(g) + 2 CO + 6 CN
E) 4 Ag(s) + 8 CN + O2(g) + 2 H2O(l) Ag3N(s) + 4 OH + AgC8(s) Answer: B
16) Chlorophyll is a green pigment involved in the growth of plants. One type of chlorophyll is a complex. What color of light should plants grow best in?
A) red B) cyan C) blue D) yellow E) green
Answer: A
17)What is the correct IUPAC name for K3[Co(NO2)6]?
A) tripotassiumhexanitritocobalt(III) B) potassium hexanitritocobaltate(III) C) potassium hexanitratocobalt(III) D) tripotassiumhexanitritocobalt(0) E) potassium hexanitritocobalt(III) Answer: B
18) In the cation [CoCl2(en)2] , the oxidation state of cobalt and its coordination number, respectively, are ________.
A) +2 and six B) -3 and two C) -4 and six D) +4 and four E) +3 and six Answer: E
19) Will magnesium metal displace Al3+[1M] ion from an aqueous solution?
Mg2+(aq) + 2 e- Mg(s) E° = -2.356 V Al3+(aq) + 3 e- Al(s) E° = -1.676 V A)Yes, since E°cell is negative.
B)No, since E°cell is negative.
C)Yes, since E°cell is positive.
D) No, the reverse reaction is spontaneous.
E) No, the system is at equilibrium.
Answer: C
20) What is the approximate pH of the H /H2 electrode compartment through which H2 gas is bubbled at a pressure of 1.00 atm if this electrode, when coupled with a Ni/(0.10 M) Ni2+ electrode, forms a galvanic cell having an initial potential of 0.10 V? [The discharge reaction involves oxidation of nickel to Ni2+. Ni2+/Ni (-0.257 V)]
A) 3.65 B) 2.15 C) 3.15 D) 4.65 E) 6.15
Answer: C
21) Which of the following magnetic/geometric descriptions is most likely for the [ZnCl4]2- ion?
A) diamagnetic/tetrahedral B) diamagnetic/octahedral C) paramagnetic/tetrahedral D) paramagnetic/square planar
E) diamagnetic/square planar Answer: A
22) For the reaction: Mg(s) + AgNO3(aq) Ag(s) + Mg(NO3)2(aq) Ag (aq) + e- Ag(s) E° = 0.800 V
Mg2+(aq) + 2 e- Mg(s) E° = -2.356 V Determine G°.
A) 609.0 kJ/mol B) -300.3 kJ/mol C) -304.5 kJ/mol D) -609.0 kJ/mol E) 304.5 kJ/mol
23) [CuCl4]2- absorbs light in the blue part of the visible spectrum, thereby appearing to have the color ________.
A) yellow B) blue C) green D) purple E) cyan
Answer: A
24) Write the correct formula for tetrachloroplatinate (II) ion.
A) [PtCl4]2- B) [PtCl3] Cl C) [PtCl2]42+ D) [Pt4Cl] E)PtCl3Cl
Answer: A
25) What mass of manganese dioxide(MnO2), from pyrolusite ore, is required for production of 25 kg of potassium permanganate(KMnO4) by a process which is 78% efficient?
A) 32 kg B) 18 kg C) 29 kg D) 25 kg E) 14 kg
Answer: B
26) List the following in order of increasing density: Ti, Pd, Nb, Pt A) Ti < Pt < Pd < Nb
B) Ti < Nb < Pd < Pt C) Nb < Ti < Pt < Pd D) Pd < Nb < Ti < Pt E) Pt < Pd < Nb < Ti Answer: B
27) Which is most probably the ground state electron configuration for the iron(III) ion?
A) [Ar]4s03d5 B) [Ar]4s03d33p3 C) [Ar]4s23d3 D) [Ar]4s04p5 E) [Ar]4s13d4 Answer: A
28) What is the cell potential for the following cell at 25°C?
Zn Zn2+ (0.0456 M) Cu2+(0.120 M) Cu Cu2+ + 2 e- Cu(s) E° = 0.340 V
Zn2+ + 2 e- Zn(s) E° = -0.763 V
A) 1.094 V B) 1.115 V C) 1.129 V D) 1.088 V E) 1.106 V
Answer: B
29) The simplified equation for the reduction of iron ore is:
Fe2O3(s) + CO(g) Fe(l) + CO2(g) When it is balanced, the coefficients are ________.
A) 1, 3, 1, 3 B) 1, 1, 2, 1 C) 2, 6, 3, 3 D) 1, 3, 2, 3 E) 1, 1, 1, 2 Answer: D
30) Write the electron configuration for Fe2+.
A) [Ar]3d6 B) [Ar]4s23d4 C) [Ar]5s2 D) [Ar]4s24p4 E) [Ar]4s14p1
Answer: A
31) Choose the INCORRECT statement.
A) Metals can be protected by cathodic protection.
B) Cathodic protection is attaching a more active metal to the protected metal.
C) Corrosion of metals is an oxidation reduction process.
D) Rust is a form of corrosion.
E) The active metal is called a sacrificial cathode.
Answer: E
32) Which of the following complexes has no geometric isomers?
A) [Co(NH3)2F4]- B) [Co(NH3)4F2]+
C)[Co(NH3)3F3]
D)[Pt(NH3)4F2]
E) [Pt(NH3)F5]-3 Answer: E
33)Which of the following species is reduced in the reaction shown below?
Cu (s) + Ag (aq) Cu2+ (aq) + Ag (s)
A)H2O (l) B)Cu (s) C) Ag (aq) D)Ag (s) E) Cu2+ (aq)
Answer: C
34) Give the correct name for [Fe(CN)6]4-.
A) iron hexacyanide B) hexacyanoferrate(III) C) hexacyanide iron(II) D) hexayanoiron(II)
E) hexacyanoferrate(II) Answer: E
35) Which of the following ions is highest in the spectrochemical series: en, I , SCN , OH , CN
A) en B) SCN C) I D) OH E) CN
Answer: E
36) For the following voltaic cell, determine the [Cl ] when PCl2 = 0.500 atm, [Zn2+] = 1.77 × 10-2 M, and Ecell = 2.250 V. The half-reactions at 25°C are:
Cl2(g) + 2 e- 2 Cl (aq) E° = +1.358 V Zn2+(aq) + 2 e- Zn(s) E° = -0.763 V Zn(s) Zn2+(aq) Cl (aq), Cl2(g) Pt(s)
A) 0.0939 M B) 2.32 × 10-3 M C) 5.48 × 10-6 M D) 0.0352 M
E) 0.0296 M
37) Which two of the following half-reactions will combine to give the galvanic cell with the highest cell potential?
1) 2 H (aq) + 2 e- H2(g) E° = 0 2) Pb2+(aq) + 2 e- Pb(s) E° = -0.125 V 3) I2(s) + 2 e- 2 I (aq) E° = +0.535 V 4) Zn2+(aq) + 2 e- Zn(s) E° = -0.763 V
A) 1 and 4 B) 2 and 4 C) 3 and 4 D) 2 and 3 E) 1 and 3
Answer: C
38) A compound has the empirical formula CoCl3 · 5NH3. One mole of it yields two moles of silver chloride when treated with silver nitrate. Ammonia is not removed by treatment with concentrated sulfuric acid. A reasonable formula for the compound is ________.
A)[Co(NH3)5]Cl3 B)CoCl3 · 5NH3 C)[Co(NH3)5Cl]Cl2 D)[Co(NH3)4Cl]Cl2 · NH3
E)[Co(NH3)4Cl2]Cl · NH3 Answer: C
39) Determine E°cell at 25 °C for the following reaction:
Pb2+(aq) + Cu(s) Cu2+(aq) + Pb(s) The half-reactions are:
Pb2+(aq) + 2 e- Pb(s) E° = -0.125 V Cu2+(aq) + 2 e- Cu(s) E° = +0.337 V
A) 0.462 V B) -0.462 V C) -0.212 V D) 0.424 V E) 0.212 V
Answer: B
40)What is the standard cell potential if the Gibbs energy is -2108 kJ in the reaction:
C3H8 + O2(g) CO2(g) + H2O(l) (not balanced)?
A) 1.092 V B) -1.092 V C) 21.85 V D) 10.92 V E) -10.92 V
Answer: A
41) Ligands approaching in a tetrahedral pattern cause some orbitals to be raised in energy. How many orbitals are on the lower energy level?
A) 1 B) 2 C) 3 D) 4 E) 5
Answer: B
42) Choose the correct shape, weak or strong field, and number of unpaired electrons for [Co(ox)3]4-.
A) tetrahedral, strong, 3 B) octahedral, strong, 5 C) square planar, strong, 3 D) tetrahedral, weak, 3
E) octahedral, weak, 3 Answer: E
43) Of the following complex ions: [CoCl(NH3)5]2+, [Co(NH3)6]3+, [Co(en)3]3+, [Co(H2O)6]3+, one appears pink, two are yellow, and one blue. Which is blue?
A) both [Co(en)3]3+ and [Co(H2O)6]3+
B) [Co(NH3)6]3+
C) [Co(en)3]3+
D) [CoCl(NH3)5]2+
E) [Co(H2O)6]3+
Answer: E
44) The correct name for [Ag(NH3)2] is ________.
A) silver ammoniate B) silver amide C) silver nitride
D) silver(I) diammine ion E) diamminesilver(I)ion Answer: E
45) [Fe(CN)6]4- has how many unpaired electrons?
A) 1 B) 2 C) 3 D) 0 E) 4
Answer: D
46) The net formation constant for tetraamminezinc(II) is 4.1 × 108. What would be the approximate potential of the galvanic cell symbolized below?
Zn/Zn(NH3)42+ (1.0 M), NH3(1.0 M)//Zn2+(1.0 M)/Zn
A) 1.02 V B) 0.76 V C) 0.00 V D) 0.51 V E) 0.25 V
Answer: E
47) In the group of elements Cr, Ni, Sn, Pt, Ti, the one which is a main group element is ________.
A) Sn B) Ni C) Ti D) Cr E) Pt
Answer: A
48) Which complex ion possesses the largest number of unpaired electrons?
A) Cr(NH3)62+
B) Fe(H2O)63+
C) Cu(NH3)42+
D) CoCl42- E) Mn(CN)64- Answer: B
49) What is the free Ag concentration of 0.020 M Ag solution mixed with an equal volume of 2.0 M NH3? Kf for [Ag(NH3)2] is 1.6 × 107.
A) 2.0 × 10-14 B) 3.1 × 10-10 C) 6.5 × 10-10 D) 6.3 × 10-8 E) 1.3 × 10-10 Answer: C
50) When 100 mL each of 2.0 × 10-4 M Ca2+ and 2.0 × 10-2 M F are mixed, what is the remaining Ca2+ ion concentration and is precipitation complete? The solubility product constant of CaF2 is 5.3 × 10-9.
A) 5.4 × 10-5, no B) 5.6 × 10-4, no C) 1.7 × 10-6, yes D) 4.3 × 10-7, no
E) 1.7 × 10-8, yes Answer: A
