Question

State why galvanization, tinning and chromeplating are used as three different processes for coating specific articles for prevention of rusting.

Answer 1

Galvanization	Iron sheets dipped in molten zinc	Iron articles which are generally exposed to heavey moisture [Iron articles which are generally exposed to heavy protects iron] [Zinc is more active than iron and forms zinc iron and hence readily than iron and hence protects iron.]
Tinning	Iron sheets dipped in molten tin.	Iron articles generally for edible applications Tinned boxes for vegetables, meat etc. [Tinning is preferred to galvanization for articles used for edible applications. Galvanised steel is not used for food containers since food acids dissolve zinc forming poisonous compounds.]
chrome plating	Iron articles electroplated with- chromium, nickel, ttin, copper, etc.	Iron articles generally- for decorative purposes, Jewellery, Cutlery, Motor-parts [Chromeplating - on a metal object can be decorative, corrosion resistant and improves surface hardness. Method is however costly and used exclusively.]