The standard emf of a galvanic cell involving cell reaction with n = 2 is found to be 0.295 V at 25oC. The equilibrium constant of the reaction would be
(Given F = 96500 C mol-1; R = 8.314 JK-1 mol-1)
2.0 × 1011
4.0 × 1012
1.0 × 102
1.0 × 1010
______ gas is the strongest oxidising agent
Oxygen
Hydrogen
Fluorine
Nitrogen
Electrical __________ in one second is equal to electrical potential multiplied by total charge passed.
Energy
Work done
Heat
Circulation
On the basis of the information available from the reaction
4/3 Al + O2 → 2/3 Al2O3, ΔG = -827 kJ mol-1 of O2, the minimum emf required to carry out the electrolysis of Al2O3 is (F = 96500 C mol-1)
2.14 V
4.28 V
6.42 V
8.56 V
There is a relationship between ___________ of the reaction and standard potential of the cell in which that reaction takes place.
Reactants
Equilibrium constant
Products
Catalyst
______________ equation is used to calculate the cell potential.
Bragg's
Ideal gas
Nernst
Solution
A hypothetical electrochemical cell is shown below
A | A+ (xM) || B+ (yM) | B
The emf measured is + 0.20 V. The cell reaction is
A + B+ → A+ + B
A+ + B → A + B+
A+ + e- → A; B+ + e- → B
The cell reaction cannot be predicted
Al2O3 is reduced by electrolysis at low potentials and high currents. If 4.0 × 104 A of current is passed through molten Al2O3 for 6 hours, what mass of aluminium is produced? (Assume 100% current efficiency, at mass of Al = 27 g mol-1)
9.0 × 103 g
8.1 × 104 g
2.4 × 105 g
1.3 × 104 g
The cell potential is the difference between the electrode potentials of the cathode and anode is called ____________
Cell emf
Electrode potential
Oxidation potential
Reduction potential
_________ is the equilibrium constant of the reaction Cu(s) + 2Ag+(aq) → Cu2+(aq) + 2Ag (s), whose Eocell = 0.46.∨
3.92 × 1015
3.29 × 1013
3.92 × 1011
3.29 × 1011
