22318.Given the data at 25°C,
Ag + I– → AgI + e– ; E° = 0.152 V
Ag → Ag+ + e–; E° = –0.800 V
What is the value of log Ksp for AgI? $\left(2.303dfrac{ ext{RT}}{ ext{F}} = 0.059 ext{ V} ight)$
–8.12
+8.612
–37.83
–16.13
22319.The quantity of electricity needed to separately electrolyze 1 M solution of ZnSO4, AlCl3 and AgNO3 completely is in the ratio of
2 : 3 : 1
2 : 1 : 1
2 : 1 : 3
2 : 2 : 1
22320.An infinite dilution of aqueous solution of BaCl2, molar conductivity of Ba2+ and Cl– ions are = 127.32 S cm2/moland 76.34 S cm2/mol respectively. What is Λ∞
m for BaCl2 at same dilute?
m for BaCl2 at same dilute?
280 S cm2mol–1
330.98 Scm2 mol–1
90.98 Scm2 mol–1
203.6 Scm2 mol–1
22321.Aqueous copper sulphate solution is electrolyzed using platinum electrodes. The electrode reaction occurring at cathode is
Cu2+(aq) + 2e– → Cu(s)
Cu(s) → Cu2+(aq) + 2e–
2H2O(l) → O2(g) + 4H+(aq) + 4e–
O2(g) + 4H+(aq) + 4e– → 2H2O(l)
22322.Zn | Zn2+ (a = 0.1M) || Fe2+ (a = 0.01M) | Fe. The emf of the above cell is 0.2905 V. Equilibrium constant for the cell reaction is
100.32/0.0591
100.32/0.0295
100.26/0.0295
e0.32/0.295
22323.Calculate the reduction potential of a half–cell containing platinum electrode immersed in 2.0 M Fe2+ and 0.02 M Fe3+.
Given Eo
Fe3+/Fe2+ = 0.771 V.
Fe3+ + e– → Fe2+
0.653 V
0.889 V
0.683 V
2.771 V
22324.Consider the following four electrodes,
P = Cu2+ (0.0001 M) | Cu(s)
Q = Cu2+ (0.1 M) | Cu(s)
R = Cu2+ (0.01 M) | Cu(s)
S = Cu2+ (0.001 M) | Cu(s)
If the standard reduction potential of Cu2+/Cu is +0.34 V, the reduction potentials in volts of the above electrodes follow the order
P > S > R > Q
S > R > Q > P
R > S > Q > P
P > Q > R > S
22325.Conductivity of 0.01 M NaCl solution is 0.00147 ohm–1cm–1. What happens to this conductivity if extra 100 ml of H2O will be added to the above solution?
Increases
Decreases
Remains unchanged
First increases and then decreases
22326.Cr2O2–
7 + I– → I2 + Cr3+
7 + I– → I2 + Cr3+
EѲ
cell = 0.79 V and EѲ of Cr2O2–
7 = 133 V. EѲ of I2 is
0.54 V
– 0.54 V
+ 0.18 V
– 0.18 V
22327.How many moles of Pt may be deposited on the cathode when 0.80 F of electricity is passed through a 1.0 M solution of Pt4+?
1.0 mol
0.20 mol
0.40 mol
0.80 mol
22328.One ampere of current is passed for 9650 seconds through molten AlCl3. What is the weight in grams of Al deposited at cathode? (Atomic weight of Al = 27)
0.9
9.0
0.09
90.0
22329.Molar ionic conductivities of a bivalent electrolyte are 57 and 73. The molar conductivity of the solution will be
130 S cm2mol–1
65 S cm2mol–1
260 S cm2mol–1
187 S cm2mol–1
22330.One Faraday of electricity is passed through molten Al2O3,aqueous solution of CuSO4 and molten NaCl taken in three different electrolytic cells connected in series. The mole ratio of Al, Cu and Na deposited at the respective cathode is
2 : 3 : 6
6 : 2 : 3
6 : 3 : 2
1 : 2 : 3
22331.Several blocks of magnesium are fixed to the bottom of a ship to
prevent action of water and salt
keep away the sharks
prevent puncturing by under–sea rocks
make the ship lighter
22332.When a lead storage battery is discharged
lead is formed
SO2is evolved
lead sulphate is consumed
sulphuric acid is consumed
22333.At 25°C molar conductance of 0.1 molar aqueous solution of ammonium hydroxide is 9.54 ohm–1cm2 mol–1 and at infinite dilution its molar conductance is 238 ohm–1cm2 mol–1. The degree of ionisation of ammonium hydroxide at the same concentration and temperature is
20.800%
4.008%
40.800%
2.080%
22334.Standard electrode potentials are:
Fe2+ | Fe (E° = –0.44 V), Fe3+ | Fe2+ (E° =0.77 V)
Fe2+, Fe3+ and Fe blocks are kept together, then
Fe3+ increases
Fe3+ decreases
Fe2+/Fe3+ remains unchanged
Fe2+ decreases
22335.The best way to prevent rusting of iron is
putting it in an acidic solution
making iron cathode
both (A) and (B)
neither (A) nor (B)
22336.The laws of electrolysis were proposed by
Fritz Haber
Michael Faraday
Friedrich Kohlrausch
Richard Abegg
22337.The electrochemical equivalent of a metal is ‘$x$’ gram–coulomb–1. The equivalent weight of metal is
$x$
$x$ × 96500
$x$/96500
1.6 × 10–19 × $x$