What is the percentage of carbon in pig iron and cast iron ?

Options

A. An electrochemical reaction (galvanic cell) is formed in which Fe acts as anode and cathode is where `O_(2)` is reduced.
B. Electrons flow from anode to cathode though the metal while ions flow through the water droplets
C. Dissolved `O_(2)` oxidises `Fe^(+2)` to `Fe^(3+)` before it is deposited as rust `(Fe_(2)O_(3)H_(2)O)`
D. All of the above take place

Answer

D

Explanation

Apply electrochemical process of corrosion iron to form hydrated ferric oxide `(Fe_(2)O_(3).xH_(2)O)`