Question

Iron nails do not get rusted when kept in distilled water even for a long time. Assign reason.

Answer 1

Step 1: Corrosion and Rusting

• Corrosion is the process when the metals get retarded because of air, moisture, and chemical changes.
• The oxidation of metals is mainly caused by oxygen in the air.
• When Iron metal is placed in the air for a long time, it gets covered by a flaky reddish-brown layer called rust, and this process is called rusting of Iron.

Step 2: Reason

• Rusting is a redox reaction formed by the reaction of iron (Fe) and oxygen (O).
• In rusting of iron, Iron undergoes oxidation while oxygen undergoes reduction.
• Compared to normal tap water, distilled water can readily absorb oxygen from the atmosphere.
• But fresh distilled water does not form rust because it does not have dissolved oxygen.
• If you keep iron nails in distilled water for over a long time, they can develop rust by absorbing oxygen from the atmosphere.
• However, if the iron nails are kept in distilled water in a closed container, they may not rust.
• Hence, iron nails do not get rusted when kept in distilled water, even for a long time when placed in a closed container.