From the following select the one which is not an example of corrosion.
The standard cell potential of the following cell $$\mathrm{Zn}\left|\mathrm{Zn}^{2+}(\mathrm{aq})\right| \mathrm{Fe}^{2+}(\mathrm{aq}) \mid \mathrm{Fe}$$ is $$0.32 \mathrm{~V}$$. Calculate the standard Gibbs energy change for the reaction:
$$\mathrm{Zn}(\mathrm{s})+\mathrm{Fe}^{2+}(\mathrm{aq}) \rightarrow \mathrm{Zn}^{2+}(\mathrm{aq})+\mathrm{Fe}(\mathrm{s})$$
(Given : $$1 \mathrm{~F}=96487 \mathrm{C}$$)
Match List I with List II.
List I (Conversion) |
List II (Number of Faraday required) |
||
---|---|---|---|
A. | 1 mole of H$$_2$$O to O$$_2$$ | I. | 3F |
B. | 1 mol of MnO$$_4^-$$ to Mn$$^{2+}$$ | II. | 2F |
C. | 1.5 mol of Ca from molten CaCl$$_2$$ | III. | 1F |
D. | 1 mol of FeO to Fe$$_2$$O$$_3$$ | IV. | 5F |
Choose the correct answer from the options given below :
Mass in grams of copper deposited by passing 9.6487 A current through a voltmeter containing copper sulphate solution for 100 seconds is (Given : Molar mass of $$\mathrm{Cu}: 63 \mathrm{~g} \mathrm{~mol}^{-1}, 1 \mathrm{~F}=96487 \mathrm{C}$$)