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प्रश्न
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because ____________.
पर्याय
Zinc is lighter than iron
Zinc has lower melting point than iron
Zinc has lower negative electrode potential than iron
Zinc has higher negative electrode potential than iron
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उत्तर
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because Zinc has higher negative electrode potential than iron.
Explanation:
`"E"_("Zn"^(2+)|"Zn")^0` = – 0.76 V and `"E"_("Fe"^(2+)|"Fe")^0` = 0.44 V
Zinc has higher negative electrode potential than iron, iron cannot be coated on zinc.
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(b) \[\ce{2H2O (1) -> O2 (g) + 4H^{+} (aq) + 4e^{-}; E^Θ_{cell} = 1.23V}\]
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(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.
(ii) In concentrated sulphuric acid solution, water will be oxidised at anode.
(iii) In dilute sulphuric acid solution, water will be oxidised at anode.
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| Column I | Column II |
| (i) Λm | (a) intensive property |
| (ii) ECell | (b) depends on number of ions/volume |
| (iii) K | (c) extensive property |
| (iv) ∆rGCell | (d) increases with dilution |
Assertion: ECell should have a positive value for the cell to function.
Reason: `"E"_("cathode") < "E"_("anode")`
