(c) dilute solution of glucose (d) chloroform 12 Which one of the following represents the same net reaction as the electrolysis of aqueous H2SO4

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1 1 Electrolysis is the process in which a chemical reaction takes place at the expense of (a) chemical energy (b) electrical energy (c) heat energy (d) none of these 2 Standard hydrogen electrode has an arbitrarily fixed potential (a) 0.00 volt (b) 1.00 volt (c) 0.10 volt (d) none of these 3 The oxidation number of chromium in K2Cr2O7 is (a) 14 (b) 12 (c) 6 (d) none of these 4 In the reaction 2 Fe + Cl2 ( 2FeCl3 (a) Fe is reduced (b) Fe is oxidized (c) Cl2 is oxidized (d) none of these 5. When fused PbBr2 is electrolyzed (a) bromine appears at cathode (b) lead is deposited at the cathode (c) lead appears at the anode (d) none of these happens 6 When aqueous solution of NaCl is electrolysed (a) Cl2 is evolved at the cathode (b) H2 is evolved at cathode (c) Na is deposited at the cathode (d) Na appears at the anode 7 During electrolysis of KNO3, H2 is evolved at (a) anode (b) cathode (c) both (a) and (b) (d) none of these 8 During electrolysis of CuSO4 (aq) using Cu electrodes Cu is deposited at (a) anode (b) cathode (c) both (a) and (b) (d) none of these 9 During electrolysis of fused NaCl, which of the following reaction occurs at anode (a) Cl ions oxidized (b) Cl ions reduced (c) Na+ ions oxidized (d) Na+ ions reduced 10 An electrochemical cell is based upon (a) acid base reaction (b) redox reaction (c) nuclear reaction (d) none of the above 11 Which one of the following will be good conductor of electricity (a) pure distilled water (b) molten NaCl (c) dilute solution of glucose (d) chloroform 12 Which one of the following represents the same net reaction as the electrolysis of aqueous H2SO4 (a) electrolysis of water (c) electrolysis of aqueous HCl (b) electrolysis of molten NaCl (d) electrolysis of aqueous NaCl 13 In a galvanic cell, the reaction occurs 2H2O ( O2 (g) + 4H+ + 4e It occurs at the (a) cathode (b) anode (c) cathode and anode (d) none of the above 14 Which statement below is not true for the reaction Fe3+ + e ( Fe2+ (a) Fe3+ is reduced (b) oxidation state of Fe has changed (c) Fe3+ can act as an oxidizing agent (d) both Fe2+ and Fe3+ are called anions AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

2 15 During a redox reaction, an oxidizing agent (a) gains electrons (b) is oxidized (c) loses electrons (d) is hydrolysed 16 In a salt bridge KCl is used because (a) it is an electrolyte (b) K+ and Cl transfer easily (c) agar agar forms a good jelly with it (d) KCl is also present in the calomel electrode 17 A oxidizing agent is a substance which brings about (a) electron donation (b) oxidation (c) reduction (d) hydrolysis 18 In the electrolysis the process of oxidation occurs at (a) anode (b) cathode (c) both cathode and anode (d) in electrolytic solution 19 In an oxidation process the oxidation number of the element (a) increases (b) decreases (c) does not change (d) everything change 20 In the reduction process the oxidation number of the element (a) increases (b) decreases (c) does not change 21 Oxidation number of oxygen in OF2 is (a) + 1 (b) 1 (c) + 2 (d) 2 22 The e.m.f. of Zn Cu cell is (a) 1.10 v (b) 1.5 v (c) 2.0 v (d) 2.5 v 23 The standard reduction potential of a standard hydrogen electrode (a) 0.0 v (b) 1.1 v (c) 1.5 v (d) 2.0 v 24 The oxidation number of Mn is K2 MnO4 is (a) + 2 (b) + 4 (c) + 6 (d) Which of the following is the definition of oxidation (a) gain of electrons (b) loss of electrons (c) addition of H2 (d) removal of O2 26 During electrolysis of H2SO4 (aq) O2 is evolved at (a) cathode (b) anode (c) both a and b (d) none of these 27 The e.m.f. produced by a voltage cell is (a) electrode potential (b) reduction potential (c) cell potential (d) oxidation potential AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

3 28 Which of the following is not a redox reaction (a) CaCO3 ( CaO + CO2 (b) Cu + 4HNO3 ( Cu(NO3)2 + 2NO2 + H2O (c) 2H2 + O2 ( 2H2O (d) MnO2 + 4HCl ( MnCl2 + Cl2 + 2H2O 29 Which element acts as a reducing agent in the reaction Zn + H2SO4 ( ZnSO4 + H2 (a) Zn (b) H (c) S (d) O 30 Which element acts as a oxidizing agent in the reaction MnO2 + 4HCl ( MnCl2 + Cl2 + 2H2O (a) Mn (b) O (c) H (d) Cl 31 When the current is passed through an electrolytic solution, which of the following process will occur (a) anions move towards anode and cations move towards cathode (b) cations and anions both move towards anode (c) cations and anions both move towards anode (d) no movement of the ions occur 32 Electric current passes through both molten and solution form of NaCl because of (a) ionic bonding (b) Na+ and Cl ions (c) ions of water (d) hydration of ions 33 A cell which produces electric current by redox reaction is called (a) standard cell (b) voltaic cell (c) reversible cell (d) concentration cell 34 Which of the following conduct electricity due to the migration of electrons only (a) copper metal (b) NaCl molten (c) NaCl (d) NaCl solution 35 Oxidation number of sulphur in S2O eq \a\co1(2,3 ) is (a) + 6 (b) 2 (c) + 2 (d) Substances through which electric current can pass are called (a) insulators (b) conductors (c) cathode (d) anode 37 Substances through which electric current cannot pass are called (a) insulators (b) conductors (c) anode (d) cathode 38 Metallic conduction is due to the (a) movement of electrons (b) movement of ions (c) both (a) and (b) (d) none of these 39 Metallic conductors conduct electricity (a) with chemical change (b) without any chemical change (c) both (a) and (b) (d) none of these 40 The flow of electrons is called (a) electrolyte (b) electric current (c) cathode (d) anode 41 A substance which in molten state or in solution form allows electric current to pass through it is called (a) electrolyte (b) insulator (c) conduction (d) none of these AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

4 42 The process in which electric current is used to carry out a non spontaneous redox reaction is called (a) electrolyte (b) electrolysis (c) metallic conductor (d) electrodes 43 In electrochemical cells, the electrode at which the reduction occurs is called (a) anode (b) cathode (c) electrolyte (d) electrolysis 44 The process of producing a chemical change in an electrolytic cell is called (a) electrolyte (b) electrolysis (c) electrodes (d) conductor 45 The process in which ionic compound when fused or dissolved in water split up into charged particles is called (a) electrolysis (b) hydration (c) ionization (d) conduction 46 An apparatus in which chemical energy in converted to electrical energy is called (a) electrolytic cell (b) galvanic cell (c) fuel cell (d) down cell 47 The metallic conductors in contact with the solution are called (a) insulator (b) electrodes (c) electrolyte (d) down cell 48 The reaction in a galvanic cell is (a) spontaneous (b) non spontaneous (c) acid base (d) none of these 49 Caustic soda is obtained by electrolysis of conc. aqueous solution of NaCl in a cell called (a) Daniell s cell (b) Nelson s cell (c) Down s cell (d) Voltaic cell 50 Sodium metal is obtained by the electrolysis of fused NaCl in a cell is called (a) Nelson s cell (b) Down s cell (c) Daniell cell (d) Voltaic cell 51 The e.m.f. of Daniell cell can be increased by (a) increasing the area of electrode (b) increasing the concentration of oxidising ion in the solution (c) increasing the concentration of reducing ion in the solution (d) adding the dil H2SO4 52 Metal and their ionic salts both conduct electricity. Which of the following statement is not correct both (a) are good conductors normally (b) are ionic in nature (c) decompose on passing current (d) are normally solid 53 The branch of chemistry which deals with the relationships between electricity and chemical reaction is called (a) chemical kinetics (b) electrochemistry (c) stiochiometry (d) thermochemistry AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

5 54 A system containing of electrodes that dips into an electrolyte in which a chemical reaction either uses or generates an electric current is called (a) voltaic cell (b) electrochemical cell (c) voltaic or galvanic cell (d) fuel cell 55 A cell in which spontaneous redox reaction generates an electric current is called (a) electrolytic cell (b) electrochemical cell (c) voltaic orgalvanic cell (d) biological cell 56 A cell in which an electric current drives a non spontaneous reaction is called (a) electrolytic cell (b) voltaic cell (c) biological cell (d) electrochemical cell 57 A process for converting one metal with a thin layer of another metal is called (a) electrolysis (b) electroplating (c) electrode potential (d) standard electrode 58 In an electrical connection between cathode and anode of a voltaic cell, electrons flow from the (a) anode to the cathode (b) cathode to the anode (c) both (a) and (b) (d) none of these 59 Greater the value of standard reduction potential of a species indicates (a) greater its tendency to accepted electrons (b) lesser tendency to accept electrons (c) greater tendency to lose electrons (d) none of these 60 In lead accumulator the electrolyte H2SO4 solution is (a) 30 % (b) 60% H2SO4 (c) 80% (d) 90% 61 In alkaline battery, the electrolyte contains (a) MnO2 (b) KOH (c) NaCl (d) NaNO3 62 Alkali metals have (a) lower value of reduction potential than coinage metals (b) higher value of reduction potential than coinage metals (c) equal values of reduction potential to coinage metals (d) none of these 63 Strong reducing agents have (a) greater positive value of standard reduction potential (b) greater negative value of standard reduction potential (c) lesser positive value of standard reduction potential (d) none of these 64 Strong oxidizing agents have (a) greater positive value of standard reduction potential (b) lesser positive value of standard reduction potential (c) greater negative value of standard reduction potential (d) none of these AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

6 65 The electrode with more negative value of reduction potential acts as (a) cathode (b) anode (c) electrode (d) none of these 66 Metals which are above SHE in electrochemical series (a) can liberate H2 from acid (b) cannot liberate H2 from acid (c) cannot always liberate H2 from acid (c) none of these 67.Corrosion reactions are (a) spontaneous redox reactions (b) non spontaneous redox reactions (c) spontaneous acid base reactions (d) none of these 68 Voltaic cell can be changed into (a) electrochemical cell (b) electrolytic cell (c) reversible cell (d) primary cell 69 Strongest oxidizing agent in the electrochemical series is (a) Li (b) F (c) H2 (d) I2 70 Strongest reducing agent in the electrochemical series is (a) Li (b) F (c) H2 (d) I2 AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

Electrochemistry Multiple Choice 71. Consider the following redox reaction: 2MnO - 4 + 3ClO - 3 + H 2 O 3ClO - 4 + 2MnO 2 + 2OH - The reducing agent is - a. H 2 O b. ClO 3 c. MnO2 d. MnO4 72.

7 Electrochemistry Multiple Choice 71. Consider the following redox reaction: 2MnO ClO H 2 O 3ClO MnO 2 + 2OH - The reducing agent is - a. H 2 O b. ClO 3 c. MnO2 d. MnO4 72. Consider the following reaction that occurs in a breathalyzer: 2Cr 2 O 7 (aq) + 16H + (aq) + 3C 2 H 5 OH (g) 4Cr 3+ (aq) + 11H 2 O (l) + 3CH 3 COOH (aq) Which atom undergoes an increase in oxidation number? a. carbon b. oxygen c. hydrogen d. chromium 73. Which of the following is the strongest reducingagent? a. Al b. Cu c. Zn d. Mg 74. Which of the following reactions is spontaneous atstandard conditions? a. Pb + Cu 2+ Cu + Pb 2+ b. H 2 + Mg 2+ Mg + 2H + c. Br 2 + 2Cl - Cl 2 + 2Br - d. 2Ag + Cu 2+ Cu + 2Ag Consider the following redox reaction: 3ClO - 2 2ClO Cl - (basic) The reduction half-reaction that occurs is A. ClO - + 2H 2 O + 4e - Cl - + 4OH - 2 B. ClO H 2 O Cl - + 4OH - + 4e - C. ClO OH - + 2e - ClO H 2 O D. ClO OH - ClO H 2 O + 2e Vanadium metal, V, reacts spontaneously with Cd 2, but not with Ti 2. Based on these results, the order of oxidizing agents, from strongest to weakest, is A. Cd 2+, V 2+, Ti 2+ B. V 2+, Ti 2+, Cd 2+ C. Ti 2+, Cd 2+, V 2+ D. Ti 2+, V 2+, Cd Consider the following electrochemical cell: In this operating electrochemical cell, a. electrons flow toward the Cu and the Cu 2 ions migrate toward the Zn. b. electrons flow toward the Cu and the Zn 2 ions migrate toward the Cu. c. electrons flow toward the Zn and the Cu 2 ions migrate toward the Zn. d. electrons flow toward the Zn and the Zn 2 ions migrate toward the Cu. 78. Which of the following affects the potentials ofelectrochemical cells? a. I and II only. b. II and III only. c. I and III only. d. I, II and III. 79. In the rusting of iron, the reduction reaction thatoccurs is a. Fe Fe e - b. Fe e - Fe c. 2H 2 O O 2 + 4H + + 4e - d. O 2 + 2H 2 O + 4e - 4OH During a cathodic protection, the sacrificial anode a. accepts electrons from the protected metal. b. reacts spontaneously with the protected metal. c. oxidizes more readily than the protected metal. d. causes the protected metal to become an anode. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

81. During the electrolysis of an aqueous solution ofki, what substance is formed at the cathode? a. iodine b. oxygen c. hydrogen d. potassium 82. When electroplating an iron medallion with nickel, a.

Which of the following represents the formation ofa stronger acid as a result of oxidation? a. H 2 SO 3 H 2 S b. HClO 4 HCl c. H - 2 SO 3 H 2 SO 4 D. HCO 3 H 2 CO 3 89.

8 81. During the electrolysis of an aqueous solution ofki, what substance is formed at the cathode? a. iodine b. oxygen c. hydrogen d. potassium 82. When electroplating an iron medallion with nickel, a. the medallion is an anode. b. the cathode is pure nickel. c. the solution contains Ni 2. d. the anode reaction is Ni 2 2e Ni 83. Which of the following represents the formation ofa stronger acid as a result of oxidation? a. H 2 SO 3 H 2 S b. HClO 4 HCl c. H - 2 SO 3 H 2 SO 4 D. HCO 3 H 2 CO Consider the following electrochemical cell: What changes occur when the cell is in operation? 84. Chlorine has an oxidation number of 5 in a. NaClO b. NaClO 2 c. NaClO 3 d. NaClO Consider the following: NO 2 N 2 O 3 The nitrogen atom in each NO 2 a. loses one electron. b. gains one electron. c. loses two electrons. d. gains two electrons. 86. Which of the following is the strongest oxidizingagent? - A. BrO 3 C. S 2 O 8 - B. ClO 4 D. Cr 2 O Consider the following half-reaction: 1 AsH 3 + H 2 O H 3 AsO 3 +? H + + e - When this half-reaction equation is balanced, the coefficient for H is a. 2 b. 3 c. 6 d When a strip of zinc is placed in a 1.0M copper (II)chloride solution, a. no change occurs. b. the [Cl increases. c. the [Cu 2 increases. d. the [Zn 2 increases. 90. A redox titration is performed in order to determine the [H 2 O 2 ].Which of the following would not be a suitable reagent to use? - A. acidified IO 3 B. acidified SO 4 - C. acidified MnO 4 D. acidified Cr 2 O Ethanol, C 2 H 5 OH, is oxidized by an acidifieddichromate solution according to the followingequation: 2Cr 2 O H + + 3C 2 H 5 OH 4Cr H 2 O + 3CH 3 COOHThe E for the reaction above is 2.98V. The E for theoxidation of ethanol is a. 0.52V b. 1.23V c. 1.75V d. 2.98V 92. Which of the following must be present to producerust by the corrosion of iron? a. I only b. II only c. I and II only d. I, II and III AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

9 93. Why can an object not be plated with magnesiumusing 1.0M MgI 2? a. Water is a stronger reducing agent than I b. Water is a stronger oxidizing agent than I c. Water is a stronger reducing agent than Mg 2 d. Water is a stronger oxidizing agent than Mg In the electrolysis of 1.0M Na 2 SO 4, what is formedat the cathode? A. O 2 B. H 2 C. H 2 SO 3 D. S 2 O Which of the following is capable of acting both asan oxidizing agent and a reducing agent? A. H + B. Na + C. Sn 2+ - D. MnO Consider the following redox reaction:c 2 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O The substance undergoing reduction is A. O 2 B. CO 2 C. H 2 O D. C 6 H 12 O The oxidation number of P in H 4 P 2 O 7 isa. -10 B. -5 C. +5 D A solution containing an unknown cation reactsspontaneously with both zinc and copper. Theunknown cation is A. 1.0M H + B. 1.0M Ag + C. 1.0M Sr 2+ D. 1.0M Mn Which of the following half-reactions is balanced? a. CIO - + H 2 O +e - Cl 2 + 2OH - b. 2CIO - + H 2 O +2e - Cl 2 + 3OH - c. 2CIO - + 2H 2 O +2e - Cl 2 + 4OH - d. 2CIO - + 2H 2 O Cl 2 + 4OH - + 2e Which of the following is a spontaneous redoxreaction? a. Ag + + I - AgI b. Ag + + Fe 2+ Ag + Fe 3+ c. 3Ag + + Au 3Ag + Au 3+ d. 2Ag + + Ni 2+ 2Ag + Ni AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

10 b a c b b b b b a b b a b d a b ca a b c a a c b b c a a a a b b a c b a a b b a b b b c b b a b b c b b b c a b a a a b a b a b a a c b a Question Answer Question Answer Question Answer 71 B 83 C 95 C 72 A 84 C 96 A 73 D 85 B 97 C 74 A 86 C 98 B 75 A 87 C 99 C 76 A 88 D 100 B 77 B 89 A 78 D 90 B 79 D 91 C 80 C 92 C 81 C 93 D 82 C 94 B AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

(c) Na is deposited at the cathode (d) Na appears at the anode

(c) Na is deposited at the cathode (d) Na appears at the anode year chemiry n0tes new CHAPTER 10 ELECTROCHEMISTRY MCQS Q.1 Electrolysis is the process in which a chemical reaction takes place at the expense of (a) chemical energy (b) electrical energy (c) heat energy