The standard emf of a galvanic cell involving cell reaction with n = 2 is found to be 0.295 V at 25o C. The equilibrium constant of the reaction would be.
(Given F = 96500 C mol-1; R =8.314 JK-1 mol-1)
2.0 x 1011
4.0 x 1012
1.0 x 102
1.0 x 1010
Standard reduction potentials at 25oC of Li+/Li,Ba2+/Ba,Na+/Na and Mg2+/Mg are -3.05,-2.90,2.71 and -2.37 volt respectively. Which one of the following is the strongest oxidising agent ?
Mg2+
Ba2+
Na+
Li+
Cell reaction is spontaneous when.
Eored is negative.
Eored is positive
is negative
is positive
A hypothetical electrochemical cell is shown below.
A + B+ A+ + B
A+ + B A + B+
A+ + e- A; B+ + e- B
the cell reaction cannot be predicted
AI2O3 is reduced by electrolysis at low potentials and high currents. If 4.0 x 104 A of current is passed through moleten AI2O3 for 6 h, what mass of aluminium is produced ? (Assume 100% current efficiency, at mass ofAI = 27 g mol-1)
9.0 x 103g
8.1 x 104g
2.4 x 105g
1.3 x 104g
On heating one end of a piece of a metal, the other end becomes hot because of.
Energised electrons moving to the other end.
Resistance of the metal.
Mobility of atoms in the metal.
Minor perturbation in the energy of atoms
The efficiency of a fuel cell is given by.
The equivalent conductances of Ba2+ and Cl- are 127 and 76 ohm-1 cm-1 eq-1 respectively at infinite dilution. The equivalent conductance of BaCI2 at infinite dilution will be.
139.52
203
279
101.5
The equilibrium of the reaction,
2.0 x 1010
4.0 x 1010
4.0 x 1015
2.4 x 1010
The most convenient method to protect the bottom of the ship made of iron is.
Coating it with red lead oxide.
White tin plating.
Connecting it with mg block.
Connecting it with Pb block.
