f.4 chem questions(rusting)

Yes it is a kind of sacrificial protection.

galvanizing 係指coat zinc on a metal surface.

scarificial protection 未必需要coating, 有接觸都ok~

Chromium plating 係electroplating...not scarificial protection,因為sacrificial protection 係由一個more reactive 既metal for protection. Chromium 係less reactive metal,佢係prevent iron from contacting with water and oxygen in air. Therefore it is not sacrificial protection

Hope that i can help you:)