The galvanized article is protected against rusting even if the zinc coating is broken. Why?

 

Asked by abcom2003 | 17th Jan, 2019, 05:11: PM

Expert Answer:

A galvanized substance is coated with a layer of zinc to delay corrosion. Zinc gets corroded itself, instead of the substance. 

The outer layer of zinc reacts with the atmospheric oxygen to form Zinc Oxide (ZnO), which is stronger than Zinc.
 
Zinc is more reactive than iron and can be easily oxidised.
When the zinc layer breaks down, zinc continues to react and gets oxidised and hence the article is protected against rusting.

Answered by Varsha | 17th Jan, 2019, 06:38: PM