A button cell used in watches functions as follows:
Zn(s) + Ag2O(s) + H2O(l) → 2Ag(s) + Zn2+(aq) + 2OH– (aq)
If half cell potentials are
Zn2+ (aq) + 2e– → Zn(s); E° = –0.76 V
Ag2O(s) + H2O(l) + 2e– → 2Ag(s)+ 2OH–(aq), E° = 0.34 V
The cell potential will be
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Aluminium displaces hydrogen from dilute HCl whereas silver does not. The E.M.F. of a cell prepared by combining Al/Al+3 and Ag/Ag+ is 2.46 V. The reduction potential of silver electrode is + 0.80 V. The reduction potential of aluminium electrode is: |
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The reduction potential values of X, Y and Z are –3.05 V, –0.44 V and –0.83 V respectively. Which of the following order is correct with respect to their reducing property? |
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For a cell reaction involving two electrons change, the standard e.m.f. of the cell is found to be 0.295 V at 25°C. The equilibrium constant of the reaction at 25°C is |
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When KMnO4 acts as an oxidizing agent and ultimately forms MnO2– |
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What is the time (in sec) required for deposition all the silver present in 125mL of 1 MAgNO3 solution by passing a current of 241.25 amperes? (1F = 96500 coulombs) |
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On the basis of the following E° values, the strongest oxidizing agent is: [Fe(CN)6]4– → [Fe(CN)6]3– + e–1; E° = –0.35 V Fe2+ → Fe3+ + e–1; E° = –0.77 V |
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A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of electrode would be |
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Accumulation of lactic acid (HC3H5O3), a monobasic acid in tissues leads to pain and a feeling of fatigue. In a 0.10 M aqueous solution, lactic acid is 3.7% dissociates. The value of dissociation constant, Ka, for this acid will be: |
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Faraday’s constant is defined as |
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A solution of nickel sulphate in which nickel rod is dipped is diluted 10 times. The reduction potential of Ni at 298 K |
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