The galvanised article protected against rusting even if the zinc coating is broken. Can you reason this out why

Sure, I can explain this.

Galvanization is a process where a protective zinc coating is applied to iron or steel to prevent rusting. The primary reason why a galvanized article remains protected against rusting even if the zinc coating is broken is due to the electrochemical nature of the galvanization process.

Here are the steps to understand this:

1. Zinc is more reactive than iron or steel. This means that zinc is more likely to give up electrons than iron or steel.

2. When the zinc coating is broken and the iron or steel underneath is exposed, the zinc will start to corrode first because it is more reactive. This is known as "sacrificial protection".

3. The zinc corrodes in preference to the iron or steel. This means that even if the coating is broken, the zinc will still corrode before the iron or steel does, thereby still offering protection against rusting.

4. This sacrificial protection continues as long as any zinc remains in the immediate vicinity of the iron or steel.

5. Therefore, even if the zinc coating is broken, the galvanized article is still protected against rusting.