Q 1.
The oxidation number of C is zero in:
(a) HCHO
(b) CH2Cl2
(c) C6H12O6
(d) all of these
Q 2.
Which of the following reactions is not a redox reaction ?
(a) NH4 + NaOH  NaCl + NH3 + H2O
(b) 4KCN + Fe(CN)2  K4[Fe(CN)6]
(c) NaIO3 + NaHSO3  NaHSO4 + Na2SO4 + I2 + H2O
(d) 2Rb + 2H2O  2RbOH + H2
Q 3.
Given G = - nFE° cell and G° = - RT In K The value of n = 2 will be given by the
slope of which line in the figure.
(a) OA
(b) OB
(c) OC
(d) OD
Q 4.
The compound which is not having oxidation number of S as + 6 :
(a) Peroxomonosulphuric acid (Caro’s acid) (b) Peroxodisuiphuric acid (Marshal’s acid)
(c) Sodiumthiosulphate (Hypo)
(d) Pyrosuiphuric acid (Oleum)
Q 5.
Which of the following compounds does not act as oxidising as well as reducing agent:
(a) HNO
(b) H2O2
(c) H2S
(d) SO2
Q 6.
The oxidation number of Cr is 6 in:
(a) Fe Cr2O4
(b) KCrO3Cl
(c) CrO5
(d) both (b) and (c)
Q 7.
When Cl2 is passed through hot NaOH, oxidation number of Cl does not changes from:
(a) -1 to 0
(b) 0 to -1
(c) 0 to +5
(d) none of these
Q 8.
Which one of the following conditions will increase the voltage of the cell represented by
the following equation ?
Zn (s) + Cu2+ (aq)  Zn2+ (aq) + Cu (s)
(a) increase in the concentration of Zn2+ (aq) ions
(b) increase in the concentration of Cu2+ (aq) ions
(c) decrease in the temperature
(d) increase in the pressure
Q 9.
Which of the following is not a redox reaction ?
(a) 3Mg + N2  Mg3N2
(b) K4 [Fe(CN)6] + H2SO4 + H2O  K2SO4 + CO + FeSO4 + (NH4)2 SO4
(c) I2 + 3Cl2  lCl3
.
(d) None of the above
Q 10. Using the following electrochemical reactions AgCl (s) + e-  Ag (s) + Cl- (aq) E° = +
0.222 V
Ag+ (aq) + e-  Ag (s), E° = + 0.799 V the value of Ksp for AgCl at 298 K
will be:
(a) 1.0 × 10-8
(b) 1.7 × 10-9
(c) 1.7 × 10-10
(d) 1.7 × 10-11
Q 11. Consider the redox reaction and choose incorrect statement : 2S2 O32  + I2  S 4O62  2 I 
(a) S2O32 gets reduced to S4O62
(c) I2 gets reduced to I-
(b) S4O32 gets oxidised to S4O62
(d) none of the above
Q 12. Which of the following have been arranged in decreasing order of oxidation number of
sulphur ?
(a) SO 2  SO42  SO32  HSO4
(b) H2SO5 > H2SO3 > SCl2 > H2S
(c) H2SO4 > SO2 > H2S > H2S2O8
(d) None of the above
Q 13. The standard reduction potential for Cu2+ /Cu is + 0.34 V. The reduction potential at pH
=14 for the above couple is [Cu2+] at pH 14 is 10-19 :
(a) - 0.22V
(b) + 0.22V
(c) - 0.34V
(d) + 0.34V
Q 14. Which among the following is not the example of autoredox reaction ?
(a) P4 + OH-  H2P O4 +PH3
(b) S2O32  SO42  S
(c) H2O2  H2O + O2
(d) AgCl + NH3  [Ag(NH3)2]Cl
Q 15. Which of the following cell reactions represent the electrolysis of water ?
(a) 2H+ + 2e-  H2(g)
(b) 2H2O  H2 (g) + 2OH(c) 4OH-  2H2O + O2(g) + 4e(d) 2H2O  O2(g) + 4H+ + 4eQ 16. Choose redox reaction among the following:
(a) FeCl3 + K4[ Fe (CN)6 ]  KCl + Fe4 [Fe (CN)6]3
(b) AgCl + Na2S2O3  Na3[Ag(S2O3)2] + NaCl
(c) NaBiO3 + MnSO4 + HNO  HMnO4 + Bi (NO3)3 + NaNO3 + Na2SO4 + H2O
(d) none of the above
Q 17. Which of the following statement is correct for ionic mobility ?
(a) It does not depends upon the voltage across the electrodes
(b) Lower the voltage, higher is the velocity
(c) Ionic velocity per unit electric field strength is constant
(d) All of the above
Q 18. If the oxidation potential be defined with reference to Ag/Ag+ half cell (for which
oxidation potential is taken to be zero), which of the following will give the correct value
of oxidation potential of Cu/Cu2+ half cell (Given that Cu/Cu2+ = - 0.34 V and Ag/Ag+ =
- 0.80 V)
(a) - 0.46 volt
(b) - 1.14 volt
(c) 1.14 volt
(d) 0.46 volt
Q 19. The equivalent conductances at infinite dilution  0  for electrolytes BA and CA are 140
and 120 S cm2 eg-1 The equivalent conductance at infinite dilution for BX is 198 S cm2
eq-1. The 0 (in S cm2 eq-1) of CX is:
(a) 178
(b) 198
(c) 218
(d) 130
Q 20. A mole of N2H2 loses 10 moles of electrons to form a new compound y. Assuming that
all the nitrogen appears in new compound, what is the oxidation state of N in y (There is
no change in oxidation number of hydrogen)
(a) - 1
(b) - 3
(c) + 3
(d) + 5
Q 21. Which of the following statement is correct ?
(a) The electrolysis of aq NaCl produces H2 gas at cathode and O2 gas at anode
(b) The electrolysis of dilute solution of NaF produces H2 gas at cathode and O2 gas at
anode
(c) The electrolysis of conc. H2SO4 produces SO2 gas at anode and O2 gas at cathode
(d) The aqueous solution of NaSO4 is acidic after electrolysis
Q 22. In an electrolytic cell, one litre of a 1 M aqueous solution of MnO4 is reduced at the
cathode. The quantity of electricity required so that the final solution is 0.1 M MnO42
will be:
(a) 0.1 F
(b) 1 F
(c) 10 F
(d) 100 F
Q 23. A galvanic cell is set up from a zinc bar weighing 100 g and 1.0 litre of 1.0 M CuSO4
solution. How long would the cell run if it is assumed to deliver a steady current of 1.0
amp. (Atomic mass of Zn = 65 ):
(a) 1.1 hr
(b) 46 hr
(c) 53.6 hr
(d) 24.00 hr
Q 24. In a reaction, 4 mole of electrons are transferred to 1 mole of HNO3. The possible product
obtained due to reduction is:
(a) 0.5 mole of N2
(b) 0.5 mole of N2O (c) 1 mole of NO2
(d) 1 mole of NH3
Q 25. Which of the following units is correctly matched ?
(a) SI unit of conductivity (k) = siemen - metre (Sm)
(b) SI units of molar conductivity = siemen metre squared per mol (Sm2 mol-1)
(c) SI unit of ionic mobility = mV-1 s-1
(d) All the above
Q 26. A current of 12 ampere is passed through an electrolytic cell containing aq. NiSO4
solution. Both Ni and H gas are formed at the cathode. The current efficiency is 60%.
What is the mass of nickel deposited on the cathode per hour ?
(a) 7.883 g
(b) 3.941 g
(c) 5.91 g
(d) 2.645 g
Q 27. An ion is reduced to the element when it absorbs 6 × 1020 electrons. The number of
equivalents of the ion is :
(a) 0.10
(b) 0.01
(c) 0.001
(d) 0.0001
Q 28. Wrong statement among the following is:
(a) The emf of a cell is the multiplication of oxidation potentials of two half cells
(b) The element with higher oxidation potential is a weak oxidising agent
(c) The emf of a cell may increase or decrease with increase in temperature
(d) The absolute value of electrode potential cannot be
Q 29. In an electrochemical. process, a salt bridge is not used :
(a) to maintain electroneutrality in each solution
(b) to complete the circuit so that current can flow
(c) as a colour indicator
(d) all of the above
Q 30. The specific conductances of four electrolytes in ohm-1 cm-1 are given below. Which one
offers hi gher resistance to passage of electric current ?
(a) 7.0×10-5
(b) 9.2 × 10-9
(c) 6.0 × 10-7
(d) 4.0 × 10-8
Q 31. 31. The reduction potential of hydrogen half-cell negative if :
(a) p (H2) = 1 atm and [H+] = 1 M
(b) p (H2) = 1 atm and [H+] = 2 M
+
(c) p (H2) = 2 atm and [H ] = 1 M
(d) p (H2) = 2 atm and [H+] = 2 M
Q 32. Which of the following does not represent the electrodes of the second kind (secondary
reference electrodes) ?
(a) Ag(s)
AgCl(s), Cl(b) Cu(s) CuSO4(aq) S O42 
(c) Hg(l)
Hg2Cl2(s), Cl-
(d) Pb(s)
PbSO4(s), S O42 
Q 33. Which of the following increases with increase concentration ?
(a) Conductance
(b) Specific conductance
(c) Equivalent conductance
(d) Molar conductance
2+
Q 34. Given standard electrode potentials Fe + 2e-  Fe;  E = 0.44 V, Fe3+ + 3e-  Fe;
 E = 0.036 V, The standard electrode potential (E°) for Fe3+ + e-  Fe2+ is
(a) - 0.476 V
(b) - 0.404 V
(c) 0.404 V
(d) + 0.772 V
Q 35. In the Zn-Cu cell, containing K2SO4 in salt bridge:
(a) conventional current flows from Zn to Cu
(b) SO flow from Zn to Cu
(c) electrons flow from Zn to Cu
(d) the weight of Zn rod increases
Answers
1.
8.
15.
22.
29.
d
b
c
a
c
2.
9.
16.
23.
30.
d
b
c
c
b
3.
10.
17.
24.
31.
b
c
c
b
c
4.
11.
18.
25.
32.
c
a
d
b
b
5.
12.
19.
26.
33.
c
b
a
a
b
6.
13.
20.
27.
34.
d
a
c
c
d
7.
14.
21
28
35.
a
d
b
b
c