Chemistry (Class - XII)

Chapter-2 : Electrochemistry

Subjective Questions
1 Mark Questions :
01. Represent the galvanic cell in which the reaction,

Zn  s   Cu 2  aq   Zn2  aq   Cu  s  takes place.

02. What is the necessity to use a salt-bridge in a Galvanic cell?

03. Express the relation among the conductivity of a solution in the cell, the cell constant and the
resistance of solution in the cell.
2 Marks Questions :
04. Define electrochemical cell. What happens when applied external potential becomes greater than
0
Ecell of electrochemical cell?

05. Using E 0 values of X and Y, predict which is better for coating the surface of iron to prevent rust and
why?

Given, 0
EFe 2
/ Fe
 0.44V , EX0 2 / X  2.36V , EY02 / Y  0.14V

06. The standard electrode potential (E0) for Daniell cell is + 1.1 V. Calculate the G 0 for the reaction.

Zn  s   Cu 2  aq   Zn2  aq   Cu  s 

(1 F = 96500 mol – 1 )
07. Explain with a graph, the variation of molar conductivity of a strong electrolyte with dilution.
08. Calculate the degree of dissociation (  ) of acetic acid if its molar conductivity (  m ) is

39.05 S cm2 mol – 1 .

Given : 0  H    349.6S cm2 mol 1 and 0  CH3COO   40.9 S cm2 mol 1 .

09. Define conductivity and molar conductivity for the solution of an electrolyte. Discuss their variation
with concentration.
10. The conductivity of 0.001 M acetic acid is 4 x 10 – 5 S/cm. Calculate the dissociation constant of acetic
acid, if molar conductivity at infinite dilution for acetic acid is 390 S cm2/mol.
11. Express the relation among cell constant, resistance of the solution in the cell and conductivity of the
solution. How is molar conductivity of a solution related to its conductivity?
2 / Electrochemistry
12. Write the name of the cell which is generally used in hearing aids. Write the reactions taking place at
the anode and the cathode of this cell.
13. Write the name of the cell which is generally used in transistors. Write the reactions taking place at the
anode and the cathode of this cell.
14. Calculate the time to deposit 1.27 g of copper at cathode when a current of 2 A was passed through
the solution of CuSO4. (Molar mass of Cu = 63.5g mol – 1 , 1 F = 96500 C mol – 1 )
15. Following reactions occur at cathode during the electrolysis of aqueous silver chloride solution:

Ag   aq   e  Ag  s  ; E 0  0.80V

1
H   aq   e  H 2  g  ; E 0  0.00V
2
On the basis of their standard reduction electrode potential (E0) values, which reaction is feasible at
the cathode and why?
16. (i) Following reactions occur at cathode during the electrolysis of aqueous copper (II) choride solution.

Cu 2  aq   2e  Cu  s  , E 0  0.34V

1
H   aq   e  H 2  g  ; E 0  0.00V
2
On the basis of their standard reduction electrode potential (E0) values, which reaction is feasible at
the cathode and why?
(ii) State Kohlrausch’s law of independent migration of ions. Write its one application.
17. What are fuel cells? Explain the electrode reactions involved in the working of H2 – O2 fuel cell.
18. How much electricity in terms of Faradays is required to produce 20 g of calcium from molten CaCl2?
19. Silver is uniformly electrodeposited on a metallic vessel of surface area of 900 cm 2 by passing a current
–3
of 0.5 A for 2h. Calculate the thickness of silver deposited. Given, the density of silver is 10.5 g cm
and atomic mass of Ag = 108 amu.
20. What type of a battery is the lead storage battery? Write the anode and the cathode reactions and the
overall reaction occurring in a lead storage battery, when current is drawn from it.
21. The chemistry of corrosion of iron is essentially an electrochemical phenomenon. Explain the reactions
occurring during the corrosion of iron in the atmosphere.
22. How many moles of mercury will be produced by electrolysing 10 M Hg (NO3)2 solution with a current
of 2.00 A for three hours? [Hg(NO3)2 = 200.6 g mol – 1 ]
23. In the electrolysis of aqueous sodium bromide, there are two possible anodic reactions.
2H 2O  l   O2  g   4H   aq   4e , E 0  1.23V
2Br   aq   Br2  g   2e , E 0  1.08 V
Which reaction occurs at anode and why?

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24. Mention the reactions occurring at
(i) anode
(ii) cathode, during working of a mercury cell.
Why does the voltage of a mercury cell remain constant during its operation?
25. Give an example of a fuel cell and write the cathode and anode reactions for it.
26. Write the overall reaction that occurs during use (discharging) of nickel – cadmium cell. Is it a primary
or a secondary cell? Mention its one merit over the lead storage cell.
3 Marks Questions :

27. (i) Calculate  r G 0 and log KC for the following cell:

Ni  s   2 Ag   aq   Ni 2  aq   2 Ag  s 
0
Given that Ecell  1.05V , 1 F = 96,500 C mol – 1
(ii) Calculate the e.m.f. of the following cell at 298 K.
Fe  s  | Fe2  0.001 M  || H   0.01M  | H 2  g 1bar  | Pt  s 
0
Given that Ecell  0.44V [log 2 = 0.3010, log 3 = 0.4771, log 10 = 1]
28. Calculate  r G 0 and log KC following reaction :
Cd 2  aq   Zn  s   Zn2  aq   Cd  s 
0
Given : ECd 2
/ Cd
 0.403V , EZn
0
2
/ Zn
 0.763
29. Calculate the standard cell potential of the galvanic cell in which the following reaction takes place:
Fe2  aq   Ag   aq   Fe3  aq   Ag  s 
Calculate the  r G 0 and equilibrium constant of the reaction also.
0
EAg 
/ Ag
 0.80V ; EFe
0
3
/ Fe2
 0.77V
30. For the cell reaction , Ni(s) | Ni2+(aq) || Ag+(aq)|Ag(s)
Calculate the equilibrium constant at 250C.
How much maximum work would be obtained by operation of this cell?
0
ENi 2
/ Ni
 0.25V ; EAg
0

/ Ag
 0.80V
31. Calculate the emf of the following cell at 250C.
Ag(s) | Ag+ (10-3M) || Cu2+(10 – 1 M) | Cu(s)
0
[Given, Ecell  0.46V and log 10n = n]
32. Determine the values of equilibrium constant (KC) and G 0 for the following reaction,
Ni  s   2 Ag   aq   Ni 2  aq   2 Ag  s 
E0 = 1.05 V, (1 F = 96500 C mol – 1 )
33. Calculate the potential for half-cell containing 0.10 M K2Cr2O7 (aq), s 0.20 M Cr3+(aq) and
1.0 x 10 – 4 M H+ (aq).
The half-cell reaction is Cr2O72  aq   14H   aq   6e  2Cr 3  aq   7 H 2O  l 
and the standard electrode potential is given as E0 = 1. 33 V
34. For the cell, Zn(s) | Zn2+(2 M) || Cu2+ (0.5 M) | Cu(s)
(i) Write the equation for each half reaction.
(ii) Calculate the cell potential at 250C.
0
[Given EZn 2
/ Zn
  0.76V , ECu
0
2
/ Cu
  0.34V ]

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35. Calculate the equilibrium constant, K, for the reaction at 298 K.
Zn  s   Cu 2  aq   Zn2  aq   Cu  s  , G0  212.300 kJ mol 1
0
[Given, EZn 2
/ Zn
  0.76V , ECu
0
2
/ Cu
  0.34V ]
36. Write the Nernst equation and compute the emf of the following cell at 298 K.
Sn(s) | Sn2+ (0.05 M) || H+(0.02 M) | H2, 1 atn | Pt
0
[ ESn 2
/ Sn
  0.144V ]
37. Conductivity of 2.5 x 10 – 4 M methanoic acid is 5.25 x 10 – 5 S cm – 1 . Calculate its molar conductivity and
degree of dissociation.
   
Given : 0 H   349.5 S cm2 mol 1 and 0 HCOO   50.5 S cm2 mol 1 .
38. The value of  of Al2(SO4)3 is 858 S cm mol
0 2 –1
, while  0m  0m SO2 is 160 S cm2 mol – 1 , calculate the
m
 4 
3+
limiting ionic conductivity of Al .
39. Calculate the degree of dissociation of acetic acid at 298 K, given that
mCH3COOH  11.7S cm2 mol 1
0m CH COO  40.9S cm2 mol 1
 3 
 m H   349.1 S cm2 mol 1
0
 
40. Chromium metal is electroplated using an acidic solution containing CrO3 according to the following
equation :
CrO3  aq   6H   6e  Cr  s   3H 2O
Calculate how many grams of chromium will electroplated by 24,000 coulombs. How long will it take
to electroplate 1.5 g chromium using 12.5 A current? [Atomic mass of Cr = 52 g mol – 1 , 1 F= 965000 C
mol – 1 ]
41. (i) The cell in which the following reaction occurs :
2Fe3  aq   2I   aq   2Fe2  aq   I 2  s 
0
has Ecell = 0.236 V at 298 K.
Calculate the standard Gibbs energy of the cell reaction.
(Given, 1F = 96500 C mol – 1 )
(ii) How many electrons flow through a metallic wire if a current of 0.5 A is passed for 2 h?
(Given, 1F = 96500 C mol – 1 )
42. (i) Calculate the mass of Ag deposited at cathode when a current of 2A was passed through a solution
of AgNO3 for 15 min.
(Given : Molar mass of Ag = 108g mol – 1 , 1F = 96500 C mol – 1 )
(ii) Define fuel cell.
43. What type of battery is lead storage battery? Write the anode and cathode reactions, and the overall
cell reaction occurring in the operation of a lead storage battery.
44. An aqueous solution of copper sulphate, CuSO4 was electrolysed between platinum electrodes using a
current of 0.1287 A for 50 min.
[Given, atomic mass of Cu = 63.5 g mol – 1 )
(i) Write the cathodic reaction.
(ii) Calculate
(a) Electric charge passed during electrolysis.
(b) Mass of copper deposited at the cathode,
[Given, 1 F = 96500 C mol – 1 ]

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 Electrochemistry /5
5 Marks Questions:
45. Calculate the emf and G for the following cell
Mg(s) | Mg2+ (0.001M)||Cu2+ (0.0001M) | Cu (s)
E 0Mg 2 / Mg   2.37V , E 0Cu2 / Cu  0.34V
   
46. Calculate the  r G 0 and emf (E) that can be obtained from the following cell under the standard
conditions at 250C.
Zn(s) | Zn2+ (aq) || Sn2+(aq) | Sn(s)
0
[Given, EZn 2
/ Zn
  0.76V , ESn
0
2
/ Sn
  0.14V and F = 96500C mol – 1 ]
47. (i) Write the formulation for the galvanic cell in which the reaction
Cu  s   2 Ag   aq   Cu 2  aq   2 Ag  s  takes place. Identify the cathode and the anode
reactions in it.
(ii) Write the Nernst equation and calculate the emf of the following cell.
Sn(s) | Sn2+ (0.04 M) || H+ (0.02 M) | H2(g) | Pt (s) (1 bar)
0
[Given ESn 2
/ Sn
  0.14V ]
48. (i) Write the cell reaction and calculate the emf of the following cell at 298 K.
Sn(s) | Sn2+ (0.004 M) || H+(0.020 M) | H2(g) (1 bar) | Pt(s)
0
(Give : ESn 2
/ Sn
= - 0.14 V0
(ii) Give reasons :
(a) On the basis of E0 values, O2 gas should be liberated at anode, but it is Cl2 gas which is liberated
in the electrolysis of aqueous NaCl.
(b) Conductivity of CH3COOH decreases on dilution.
49. (a) A steady current of 2 amperes was passed through two electrolytic cells X and Y connected in series
containing electrolytes FeSO4 and ZnSO4 until 2.8 g of Fe deposited at the cathode of cell X.
How long did the current flow? Calculate the mass of Zn deposited at the cathode of cell Y.
(Molar mass : Fe = 56 g mol-1, Zn = 65.3 g mol – 1 , 1 F = 96500 C mol-1)
(b) In the plot of molar conductivity (  m ) vs square root of concentration (C1/2), following curves are
obtained for two electrolytes A and B.

Answer the following

(i) Predict the nature of electrolytes A and B.
(ii) What happens on extrapolation of  m to concentration approaching zero for electrolytes A and B?
50. (i) Define the following terms:
(a) Molar conductivity (  m )
(b) Secondary batteries
(c) Fuel cell

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6 / Electrochemistry
(ii) State the following laws:
(a) Faraday’s first law of electrolysis
(b) Kohlarausch’s law of independent migration of ions.
Assertion – Reason
Direction (Q. Nos. 51 to 54) : Each of these equations contains two statements: Assertion and Reason. Each
of these questions also has four alternative choices, only one of which is the correct answer. You have to
select one of the codes (a), (b), (c), (d) given below.
(a) Both Assertion (A) and Reason (R) are correct statements, and Reason (R) is the correct explanation
of the Assertion (A).
(b) Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct
explanation of the Assertion (A).
(c) Assertion (A) is correct, but Reason (R) is incorrect statement.
(d) Assertion (A) is incorrect, but Reason (R) is correct statement.
51. Assertion (A) : Conductivity of an electrolyte increases with decrease in concentration.
Reason (R) : Number of ions per unit volume decreases on dilution.
52. Assertion (A) : In a Daniell cell, if concentrations of Cu2+ and Zn2+ ions are doubled, the emf of the cell
will be doubled.
Reason (R) : If the concentration of ions in contact with the metal is doubled, the electrode potential
will be doubled.
53. Assertion (A) : For the Daniell cell, Zn|Zn2+||Cu2+|Cu with Ecell = 1.1 V, the application of opposite
potential is greater than 1.1 V results into flow of electrons from cathode to anode.
Reason (R) : Zn is deposited at anode and Cu is deposited at cathode.
54. Assertion (A) : As a lead storage battery gets discharged, density of electrolyte present in it decreases.
Reason (R) : Lead and lead dioxide both react with sulphuric acid to form lead sulphate.
CASE STUDY
(Read the passage given below and answer the following questions)
Case I : Molar conductivity,  m is defined as the conducting power of all the ions produced by
dissolving one gram mole of an electrolyte in solution.
It is related to conductivity (or specific conductance),  as follows:

Molar conductivity,  m (Greek lambda) =
C
In the above equation, if  is expressed in 8 m – 1 and the concentration C in mol m – 3, then the units
of  m are in S m2 mol – 1 .
Now, 1 mol m – 3 = molarity (mol/L) x 100 L / m3
Hence,  m (S m2 mol – 1 ) =  (S m – 1 ) / molarity (mol L – 1) x 1000 Lm – 3 .
If  is expressed in Scm-1 and C in mol cm-3, then the units for  m are S cm2 mol – 1
. It can be
calculated by using the equation:
   Scm1  100cm3 / L 
  S cm mol 
2 1

 molarity  mol / L  
 
Both type of units are used in literature and are related to each other by the equations:
1 S m2 mol – 1 = 104S cm2 mol – 1

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 Electrochemistry /7
1 S cm2 mol – 1 = 10-4S cm2 mol – 1
Equivalent conductance  eq (lambda). It is defined as the conducting power of all the ionsproduced by
dissolving one gram equivalent of an electrolyte in solution.
55. The molar conductivity of a 1.5 M solution of an electrolyte is found to be 138.9 Scm2 mol – 1 . Calculate
the conductivity of the solution.
56. Why does the conductivity of a solution decreases with dilution.
57. How is the unit of molar conductivity arrived?
58. Express mathematically, the relationship among the degree of dissociation of an electrolyte and its
molar conductance.
OR
What is the effect of decreasing concentration on the molar conductivity of a weak electrolyte?

Case II : Conductivity of silicon increases if it is doped with certain other elements. Doping means
introduction of small amount of impurities like phosphorus, arsenic or boron into the pure crystal.
When a silicon crystal is doped with a group 15 element (with five valence electrons) such as, P, As, Sb
or Bi, the structure of the crystal lattice remains unchanged.
Out of the five valence electrons of group 15 doped element, four electrons are used in normal
covalent bonding with silicon, while fifth electron is dilocalised and thus conducts electricity.
Doping a silicon crystal with a group 13 element (with three valence electrons) such as B, Al, Ga or In
produces a semiconductor with three electrons in dopant.
59. Why phosphorus is doped with silicon to make semiconductor?
(a) To increase the melting point of silicon
(b) Their conductance range is in between conductor and semiconductor
(c) They belong to same period
(d) All of the above
60. Theadvantage of heating a germanium semiconductor with ‘X’ metal to increase conductivity. Identify
metal ‘X’.
(a) Indium (b) Boron (c) Assenic (d) Silver
61. Fe3O4 becomes paramagnetic at 850 K but ferromagnetic at room temperature because
(a) heating increases randomisation of spins
(b) Increase in temperature increase the kinetic energy
(c) heating decreases the motion of the electrons
(d) all the electrons get paired on heating
62. If NaCl is doped with 10 – 5 and % SrCl2, what is the concentration of cation vacancies?
(a) 2.07 x 10 – 2 mol – 1 (b) 6.02 x 1016 mol – 1
12 –1
(c) 2.07 x 10 mol (d) 3.14 x 1017 mol – 1
OR
Solids with F-centre having vacancy which is filled with
(a) a pair of electrons (b) unpaired electrons
(c) a positive ion (d) divalent cation

Case III : The standard potentials are always measured under standard conditions, i.e., when the
pressure of a gas is 1 atm, concentration of ions is 1 mol dm -3 and the temperature is 298 K. However,

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8 / Electrochemistry
practically standard conditions are hardly achieved or used. The potential of the electrode whose
reaction can be written (in the form or reduction) as
M n  aq   ne  M  s 
which is measured against standard hydrogen electrode, is written as

E M n / M  E 0M n / m 
RT
In
M 
    nF [M n ]
This is known as the Nernst equation.
63. Write Nernst equation for the following cell reaction:
Zn | Zn2+ (aq) || Cu2+ (aq)| Cu(s)
64. What is the effect of increase in concentration of zinc ions on the electrode potential of zinc electrode
 
for which EZn2 / Zn equals – 0.76 V?
65. How can the reduction potential of an electrode increased?
66. What does the standard electrode potential of a metal being negative E 0
Zn2 / Zn 
 0.7632.
indicate?
OR
How does temperature affect Nernst equation?

Multiple Choice Questions

1. Which cell will measure standard electrode potential of copper electrode?

(i) Pt  s  | H 2  g.0.1bar  | H   aq.,1 M  || Cu 2  aq.,1M  | Cu

(ii) Pt  s  | H 2  g.1bar  | H   aq.,1 M  || Cu 2  aq., 2M  | Cu

(iii) Pt  s  | H 2  g.1bar  | H   aq.,1 M  || Cu 2  aq.,1M  | Cu

(iv) Pt  s  | H 2  g.1bar  | H   aq.,0.1 M  || Cu 2  aq.,1M  | Cu

2. Electrode potential for Mg electrode varies according to the equation

0.059 1

EMg 2 |mg  EMg 2  log the graph of log  Mg 2  is
|Mg
2  Mg 
2

(i) (ii)

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(iii) (iv)
3. Which of the following statement is correct?
(i) ECell and  rG of cell reaction both are extensive properties.
(ii) ECell and  rG of cell reaction both are intensive properties.
(iii) ECell is an intensive property while ΔrG of cell reaction is an extensive property.
(iv) ECell is an extensive property while ΔrG of cell reaction is an intensive property.
4. The difference between the electrode potentials of two electrodes when no current is drawn through
the cell is called ___________.
(i) Cell potential (ii) Cell emf
(iii) Potential difference
(iv) Cell voltage
5. Which of the following statement is not correct about an inert electrode in a cell?
(i) It does not participate in the cell reaction.
(ii) It provides surface either for oxidation or for reduction reaction.
(iii) It provides surface for conduction of electrons.
(iv) It provides surface for redox reaction.
6. An electrochemical cell can behave like an electrolytic cell when ____________
(i) Ecell  0 (ii) Ecell  Eext (iii) Eext  Ecell (iv) Ecell  Eext

7. Which of the statements about solutions of electrolytes is not correct?

(i) Conductivity of solution depends upon size of ions.
(ii) Conductivity depends upon viscosiy of solution.
(iii) Conductivity does not depend upon solvation of ions present in solution.
(iv) Conductivity of solution increases with temperature.
8. Using the data given below find out the strongest reducing agent.

ECr O2 / Cr 3
 1.33V ECl / Cl 
 1.36V
2 7 2

 
EMnO 
/ Mn2
 1.51V ECr 3
/ Cr
 0.74V
4

(i) Cl  (ii) Cr (iii) Cr 3 (iv) Mn2

9. Use the data given in Q.8 and find out which of the following is the strongest oxidising agent.
(i) Cl  (ii) Mn2 (iii) MnO4 (iv) Cr 3
10. Using the data given in Q.8 find out in which option the order of reducing power is correct.
(i) Cr 3  Cl   Mn2  Cr (ii) Mn2  Cl   Cr 3  Cr
(iii) Cr 3  Cl   Cr2O72  MnO4 (iv) Mn2  Cr 3  Cl 1  Cr
11. Use the data given in Q.8 and find out the most stable ion in its reduced form.
(i) Cl  (ii) Cr 3 (iii) Cr (iv) Mn2
12. Use the data of Q.8 and find out the most stable oxidised species.
(i) Cr 3 (ii) MnO4 (iii) Cr2O72 (iv) Mn2

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10 / Electrochemistry
13. The quantity of charge required to obtain one mole of aluminium from Al2O3 is ___________.
(i) 1F (ii) 6F (iii) 3F (iv) 2F
14. The cell constant of a conductivity cell _____________.
(i) changes with change of electrolyte.
(ii) changes with change of concentration of electrolyte.
(iii) changes with temperature of electrolyte.
(iv) remains constant for a cell.
15. While charging the lead storage battery ______________.
(i) PbSO4 anode is reduced to Pb. (ii) PbSO4 cathode is reduced to Pb.
(iii) PbSO4 cathode is oxidised to Pb. (iv) PbSO4 anode is oxidised to PbO2.
16.  m NH OH  is equal to ______________.
0
4

(i) 0m NH OH   0m NH Cl   0HCl  (ii) 0m NH Cl   0m NHOH   0NaCl 

4 4 4

(iii) 0m NH Cl   0m NaCl   0NHOH  (iv) 0m NaOH   0m NaCl   0NH Cl 
4 4

17. In the electrolysis of aqueous sodium chloride solution which of the half cell reaction will occur at
anode?
(i) Na   aq   e  Na  s  ; ECell 
 2.71V
(ii) 2H 2O  l   O2  g   4H   aq   4e ; ECell

 1.23V
1
(iii) H   aq   e  H 2  g  ; ECell

 0.00V
2
1
(iv) Cl   aq   Cl2  g   e ; ECell

 1.36 V
2

II. Multiple Choice Questions (Type-II)

Note : In the following questions two or more than two options may be correct.
18. The positive value of the standard electrode potential of Cu2+/Cu indicates that ____________.
(i) this redox couple is a stronger reducing agent than the H+/H2 couple.
(ii) this redox couple is a stronger oxidising agent than H+/H2.
(iii) Cu can displace H2 from acid.
(iv) Cu cannot displace H2 from acid.

19. ECell for some half cell reactions are given below. On the basis of these mark the correct answer.
1
(a) H   aq   e  H2  g ; 
ECell  0.00 V
2
(b) 2H 2O  l   O2  g  4H   aq   4e 
ECell  1.23 V
(c) 2SO42  aq   S2O82  aq   2e 
ECell  1.96 V
(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.
(ii) In concentrated sulphuric acid solution, water will be oxidised at anode.
(iii) In dilute sulphuric acid solution, water will be oxidised at anode.

(iv) In dilute sulphuric acid solution, SO42 will be oxidised to tetrathionate ion at anode.

20. ECell  1.1 V for Daniel cell. Which of the following expressions are correct description of state of
equilibrium in this cell?
2.303RT 2.2
(i) 1.1  Kc (b) log Kc  1.1 (c) log K c  (d) log Kc  1.1
2F 0.059

NALANDA PUBLIC SCHOOL, SECTOR – 8, CDA, CUTTACK

 Electrochemistry /11
21. Conductivity of an electrolytic solution depends on ____________.
(i) nature of electrolyte.
(ii) concentration of electrolyte.
(iii) power of AC source.
(iv) distance between the electrodes.
22. 0m  H 2O is equal to ______________.
(i) 0m HCl   0m NaOH   0m NaCl 
(ii) 0m HNO   0m NaNO   0m NaOH 
3 3

(iii) 0HNO   0m NaOH   0m NaNO 

3 3

(iv) 0m NH OH   0m HCl   0m NH Cl 

4 4

23. What will happen during the electrolysis of aqueous solution of CuSO4 by using platinum electrodes?
(i) Copper will deposit at cathode.
(ii) Copper will deposit at anode.
(iii) Oxygen will be released at anode.
(iv) Copper will dissolve at anode.
24. What will happen during the electrolysis of aqueous solution of CuSO4 in the presence of Cu
electrodes?
(i) Copper will deposit at cathode.
(ii) Copper will dissolve at anode.
(iii) Oxygen will be released at anode.
(iv) Copper will deposit at anode.
25. Conductivity κ , is equal to ____________.
1 1 G 1
(i) (ii) (iii)  m (iv)
RA R A
26. Molar conductivity of ionic solution depends on ___________.
(i) temperature.
(ii) distance between electrodes.
(iii) concentration of electrolytes in solution.
(iv) surface area of electrodes.
27. For the given cell, Mg|Mg2+|| Cu2+|Cu
(i) Mg is cathode
(ii) Cu is cathode
(iii) The cell reaction is Mg + Cu2+  Mg2+ + Cu
(iv) Cu is the oxidising agent

NALANDA PUBLIC SCHOOL, SECTOR – 8, CDA, CUTTACK