Q.1.
Given electrode potentials Fe3+ + e → Fe2+ , E=0.771 voltsI2 + 2e → 2I- , E=-0.536 voltsEcell for reaction 2Fe3+ + 2I- → 2Fe2+ + I2 is [ AIIMS 1994]
-
0%
a) (2 × 0.0771) - 0.536)=1.006 volts
-
33%
b) (0.771 - 0.5×0.536)=0.503 volt
-
67%
c)0.771 - 0.536=0.235 volt
-
0%
d)0.536 - 0.771=-0.235 volt
Q.2.
The most durable metal plating on iron to protect against corrosion is [ CBSE PMT 1994]
-
0%
a) Nickel plating
-
22%
b) Copper plating
-
22%
c)Tin plating
-
56%
d)Zinc plating
Q.3.
How many coulombs of electricity are required for reduction of 1 mole of MnO4- to Mn2+ ?
-
29%
a) 96500 C
-
0%
b) 1.93 × 105 C
-
43%
c) 4.83 × 104
-
29%
d) 1.93 × 102
Q.4.
A Cell constant is generally found by measuring the conductivity of aqueous solution of ..[ MP PET 1991]
-
0%
a)BaCl2
-
33%
b) KCl
-
50%
c)NaCl
-
17%
d)MgCl2
Q.5.
Reaction occurring at cathode is [ CPMT 1991]
-
0%
a) Hydrolysis
-
0%
b) Neutralisation
-
57%
c)Oxidation
-
43%
d)Reduction
Q.6.
1.08g of pure silver was converted into silver nitrate and its solution was taken in a beaker. It was electrolysed using platinum cathode and silver anode, 0.01Faraday of electricity was passed using 0.15Volt above the decomposition potential of silver. the silver content of the beaker after the above shall be [ Pb. CET 1995]
-
43%
a) 0 g
-
29%
b) 0.108 g
-
14%
c)0.0108 g
-
14%
d)1.08g
Q.7.
An electrochemical cell is set up as followsPt(H2, 1atm)/0.1M HCl/0.1 acetic acid/(H2, 1atm)PtEMF of cell will not zero because [ CBSE PMT 1995]
-
14%
a) the temperature of this cell will not be zero because
-
29%
b) the pH of 0.1M HCl and 0.1M acetic acid is not the same
-
43%
c) acid used in two different compartments are different
-
14%
d) EMF of a cell depends on molarities of acid used
Q.8.
Which one of the following reaction is not possible? [ MP PMT 1991]
-
14%
a)Fe + H2SO4 → FeSO4 + H2
-
29%
b) Cu +AgNO3 → Cu(NO3)2 + 2Ag
-
43%
c)2KBr + I2 → 2KI + Br2
-
14%
d)CuO + H2 → Cu + H2O
Q.9.
If the pressure of hydrogen gas is increased from 1atm to 100atm, keeping the hydrogen ion concentration constant at 1M, the voltage of the hydrogen half-cell is at 25°C will be
-
29%
a) 0.059 V
-
14%
b) -0.059 V
-
57%
c)0.295 V
-
0%
d)0.118 V
Explanation
Q.10.
the standard electrode potential of two half cells are given belowNi2+ + 2e-=Ni Eo=-0.25 voltZn2+ + 2e-=Zn, Eo=-0.77 voltsThe voltage of cell formed by combining the two half cells would be ..[ BHU 1987]
-
14%
a)- 1.02 volts
-
57%
b) +0.52 volts
-
14%
c)+1.02 volts
-
14%
d)-0.52 volts
Q.11.
electrolytic conduction differs from metallic conduction in the fact in the case of electrolytic conduction [ Bihar CEE1992]
-
0%
a) the resistance increases with increasing temperature
-
50%
b) the resistance decreases with increasing temperature
-
17%
c) the flow of current does not generate heat
-
33%
d) the resistance is independent of the length of the conductor
Q.12.
Electrode potential (Ered) of 4 elements A, B, C , D are -1.36, -0.32, 0, -1.26V respectively. The decreasing reactivity order of these elements is [ MP PMT 1995]
-
0%
a)A, D, B and C
-
50%
b) C, B, D and A
-
50%
c)B, D, C and A
-
0%
d)C, A, D, and B
Q.13.
The potential of the cell containing two hydrogen electrodes as represented belowPt, H2(g) | H+(10-6M)||H+(10-4M) |H2(g), Pt at 298K is
-
0%
a) 0.118V
-
17%
b) -0.0591V
-
33%
c)0.118V
-
50%
d)0.0591V
Explanation
Q.14.
The standard reduction potential for the two half-cell reactions are given belowCd2+(aq) + 2e- → Sd(s) , E°=-0.40VAg+(aq) + e- → Ag(s) E°=0.80VThe standard free energy change for the reaction 2Ag+9aq) + Cd(s) → 2Ag(s) + Cd2+(aq) is given by [kerala MEE 2003]
-
0%
a) 115.8 kJ
-
22%
b) -115.8 kJ
-
56%
c)-231.6 kJ
-
22%
d)231.6 kJ
Q.15.
Solubility of a sparingly soluble salt S, specific conductance, K and the equivalent conductance Λo are related as
-
0%
a)
-
0%
b)
-
100%
c)
-
0%
d) S=KΛo
Explanation
Q.16.
Which one of the following reaction occurs at the cathode? [ CPMT 1995]
-
0%
a)2OH- → H2O + O + 2e-
-
17%
b) Ag → Ag+ + e-
-
17%
c)Fe2+ → Fe3+ + e-
-
67%
d)Cu2+ + 2e- → Cu
Q.17.
What is the value of E forH2O| H2(1 atm)|pt at 298K
-
0%
a) -0.207V
-
33%
b) +0.207V
-
33%
c)-0.414 V
-
33%
d)+0.414V
Explanation
Q.18.
Which of the following will form the cathode with respect to iron anode in an electrolyte cell [ AMU 1997]
-
17%
a) Mg
-
0%
b) Al
-
67%
c)Cu
-
17%
d)An
Q.19.
The oxidation potential of 0.05M H2SO4 is [ Manipal PMT 2002]
-
0%
a) -2×0.0591
-
0%
b) -.01×0.0595
-
71%
c) -2.321×0.0591
-
29%
d) +1×0.0591
Explanation
Q.20.
The standard emf for the cell reaction2Cu+(aq) → Cu + Cu2+is +0.36 V at 298KThe equilibrium constant for the reaction is ..[Orissa JEE 2003]
-
0%
a) 5 ×106
-
17%
b) 1.4 ×1012
-
33%
c)7.4 ×1012
-
50%
d)1.2 ×106
Explanation
Q.21.
Standard electrode potential data are useful for understanding the suitability of an oxidant in a redox titration. Some half-sell reactions and their standard potentials are given belowMnO4- + 8H+(aq) + 5e- → Mn2+(aq) + 4H2O(l), E°=1.41VCr2O72-(aq) + 14H+(aq) + 6e- → 2Cr3+(aq) + 7H2O9l), E°=1.38VFe3+(aq) + e- → Fe2+(aq) , E°=0.77VCl2(g) + 2e- → 2Cl-(aq), E°=1.4VIdentify the only incorrect statement regarding the quantitative estimation of aqueous Fe(NO3)2 [ IIT 2002]
-
14%
a)MnO4- can be used in aqueous HCl
-
43%
b) Cr2O72- can be used in aqueous HCl
-
14%
c) MnO4- can be used in aqueous H2SO4
-
29%
d) Cr2O72- can be used in aqueous H2SO4
Q.22.
Which of the following statement is correct? [ MP PET 1998]
-
0%
a) Oxidation number of oxygen in KO2 is +1
-
60%
b) The specific conductance of an electrolyte solution decreases with increase in dilution
-
20%
c) Sn2+ oxidises Fe3+
-
20%
d) Zn/ZnSO4 is a reference electrode
Q.23.
Standard potential (Eo) for some half-reactions are given below Sn4+ + 2e- → Sn2+ , E0=+0.15V 2Hg2+ + 2e → Hg22+; Eo=0.92V PbO2 + 4H+ +2e- → Pb2+ + 2H2O; Eo=+1.45V Based on the above, which one of the following statement is correct? [ CBSE PMT 1997]
-
0%
a)Sn4+ is a stronger oxidising agent than Pb4+
-
60%
b) Sn2+ is a stronger reducing agent than Hg22+; Eo
-
20%
c)Pb2+ is a stronger oxidising agent than Pb4+
-
20%
d)Pb2+ is stronger reducing agent than Sn2+
Q.24.
Conductivity ( unit Siemen's S) is directly proportional to area of the vessel and the concentration of the solution in it and inversely proportional to the length of the vessel, then the unit of constant of proportionality is ..[AIEEE 2002]
-
0%
a) S m mol-1
-
50%
b) S m2 mol-1
-
50%
c)S-2 m2 mol
-
0%
d)S2 m2 mol-2
Explanation
Q.25.
The emf of Danielle cell is 1.1V. If the value of Faraday is 96500 coulombs per mole, the change in free energy in kJ is [ Pb. CET 1995]
-
20%
a)212.30
-
20%
b) -212.3
-
40%
c)106.15
-
20%
d)-106.15
Q.26.
Choose the correct statement from the following which is related to the electrochemical series .. [ CPMT 1998]
-
20%
a) Electrochemical series is not the arrangement of metals and ions according to their reactivity
-
0%
b) The metals ions at the top of the electrochemical series are highly electronegative
-
60%
c) Strongly electropositive metals can displace weakly electropositive metals from their salt solution
-
20%
d) All metals above hydrogen in the series do not displace hydrogen from dilute acids
Q.27.
Which of the following is the use of electrolysis?
-
0%
a)Electroplating
-
0%
b) Electrorefining
-
60%
c)Both A and B
-
40%
d)None of the above
Q.28.
The standard reduction potential value of the three metallic cations X, Y and Z are 0.52, -3.03 and -1.18 V respectively. the order of reducing power of the corresponding metals is [ IIT 1998]
-
25%
a) Y > Z > X
-
0%
b) X > Y > Z
-
75%
c)Z > Y > X
-
0%
d)Z > X > Y
Q.29.
Ionic mobility of Ag+ is...λAg=5 ×10-4 ohm-1cm2 eq-1)[ orissa JEE 2003]
-
25%
a) 5.2 ×10-19
-
0%
b) 2.4 ×10-9
-
50%
c)1.52 ×10-9
-
25%
d)8.52 × 10-9
Q.30.
The potential of Hydrogen electrode at pH=10 and 25°C is
-
0%
a) 0.59 V
-
33%
b) Zero
-
50%
c) -0.59V
-
17%
d) -0.059 V
Explanation
