Why is FeCl3 the product, when Fe and Cl2 reacts and not FeCl2?
2 Answers
When iron is heated in a stream of dry chlorine the product is iron(III) chloride. This happens because chlorine is a powerful oxidising agent so brings out the higher oxidation state of iron:
To make iron(II) chloride you can react XS iron with dilute hydrochloric acid:
The extra stability of
This is exactly half of the maximum number (10) that can be accommodated, so it represents a particularly stable situation.