What happens to an iron nail when placed in a salt solution

What happens to an iron nail when placed in a salt solution when trying to conduct electricity? Why do these changes occur and describe what happens when a iron nail rusts?

Solution

If an iron nail is placed in salt solution when trying to conduct electricity bubbles appear on the surface

as chlorine gas comes out of the solution

the voltage difference between the two ends of the nail cause Na+ to be attracted towards lower voltage end and

cl - to the lower pote ntial end

similarly H+ goes to the higher potential end and OH- to the lower potential end.

in the higher potential H+ gets reduced to form hydrogen gas and in the lower potential CL- gets oxidised to form chlorine gas and at the same time Fe 2+ gets reduced and iron metal is precipitated.

In case of rusted Iron there would be no Iron precipitated. as no Fe2+ gets reduced.