Corrosion of iron is essentially an electrochemical phenomenon where the cell reactions are

Monjur Alahi

Corrosion of iron is essentially an electrochemical phenomenon where the cell reactions are
A. Fe is oxidised to `Fe^(2+)` and dissolved oxygen in water is reduced to `OH^(-)`
B. (b) Fe is oxidised to `Fe^(3+)` and `H_(2)O` is reduced to `O_(2)^(2-)`
C. Fe is oxidised to `Fe^(2+)` and `H_(2)O` is reduced to `O_(2)^(-)`
D. Fe is oxidised to `Fe^(2+)` and `H_(2)O` is reduced to `O_(2)`


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Salim Ahmed Kawsar

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Correct Answer - A
(a) Al anode : `Fe to Fe^(2+)+2e^(-)xx2`.
`("Al cathode" : O_(2)+2H_(2)O+4e^(-) to 4OH^(-))/("Overall reaction" , 2Fe+O_(2)+2H_(2)O to 2Fe(OH)_(2))`
`:.` It is the correct option.

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