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
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.
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
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.
Standard electrode potentials are
Fe3+ increases
Fe3+ decreases
remains unchanged
Fe2+ decreases
The efficiency of a fuel cell is given by.
Given,
0.52 V
0.90 V
0.30 V
0.38 V
The equivalent conductance of solution of a weak monobasic acid is 8.0 mho cm2 and at infinite dilution is 400 mho cm2.
1.25 x 10-5
1.25 x 10-6
6.25 x 10-4
1.25 x 10-4
