In electrolysis of NaCI when Pt electrode is taken then H2 is liberated at cathode while with Hg cathode it forms sodium amalgam because.
Hg is more inert than Pt.
More voltage is required to reduce H+ at Hg than at Pt.
Na is dissolved in Hg while it does not dissolved in Pt.
Concentration of H+ ions is larger when Pt electrode is taken.
The specific conductance of 0.1 NKCI solution at 23oC is 0.012 ohm-1 cm-1. The resistance of cell containing the solution at the same temperature was found to be 55 ohm. The cell constant will be.
0.142 cm-1
0.66cm-1
0.918cm-1
1.12 cm-1
AI2o3 is reduced by electrolysis at low potentials and high currents. If 4.0 x 104 A of current is passed through molten AI2O3for 6 h, what mass of aluminium is produced ? (Assume 100% current efficiency, at mass of AI = 27 g mol-1)
9.0 x 103g
8.1 x 104g
2.4 x 105g
1.3 x 104g
On the basis of the following Eovalues, the strongest oxidising agent is.
[Fe(CN)6]4-
Fe2+
Fe3+
[Fe(CN)6]3
4.5 g of aluminium (at.mass 27 u) is deposited at cathode from AI3+ solution by a certain quantity of electric charge. The volume of hydrogen produced at STP from H+ ions in solution by the same quantity of electric charge will be
44.8 L
22.4 L
11.2 L
5.6 L
Which one of the following pairs of substances on reaction will not evolve H2 gas.
Iron and H2SO4 (aqueous).
Iron and steam.
Copper and HCI (aqueous).
Sodium and ethyl alcohol.
Kohlrausch's law states that at.
Finite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte .
Infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte depending on the nature of the other ion of the electrolyte.
Infinite dilution, each ion makes definite contribution to conductance of an electrolyte , whatever be the nature of the other ion of the electrolyte.
Infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte. whatever be the nature of the other ion of the electrolyte.
An electrochemical cell is shown below;
Pt,H2[1atm]/HCI (0.1M)//CH3COOH(0.1M)H2(1atm),Pt. The emf of the cell will not be zero, because
Emf depends on molarities of acids used.
pH of 0.1 M HCI and 0.1 M CH3COOH is not same
The temperature is constant.
Acids used in two compartments are different.
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
Cu+(aq) is unstable in solution and undergoes simultaneous oxidation and reduction according to the reaction.
-0.38 V
+0.49 V
+0.38V
-0.19V
