(a) State and explain Kohlrausch law. (b) How much electricity in terms of Faradays is required to produce 20 g of calcium from molten CaCl2? -Chemistry

(a) State and explain Kohlrausch law. (b) How much electricity in terms of Faradays is required to produce 20 g of calcium from molten CaCl2? -Chemistry
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a) Corrosion is an electrochemical phenomenon. At a particular spot of iron j oxidation it takes place and the spot behaves j as anode and the reaction will be: i At anode : 2Fe(s) → 2Fe2+ + 4e– Electrons released above move through the metal to another spot and reduce oxygen in presence of H+ and the spot behaves as cathode with the reaction. At cathode : O2(g) + 4H+ (aq) + 4e– → 2H2O(I) Overall reaction : 2Fe(s) + O2(g) + H+(aq) → 2Fe2+(aq) + 2H2O (l) The ferrous ions are further oxidised by atmospheric oxygen to form hydrated ferric oxide (Fe2O3 xH2O) as rust. (b) Ca22+ + 2e– → Ca Thus, 1 mole of Ca i.e. 40 g of Ca requires electricity = 2F ∴ 20 g of Ca will require electricity = 1F
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