Vr/hen HCI reacts with finely powdered iron, it forms ferrouschloride, and not ferric chloride. Explain, why ?

The reaction between hydrochloric acid (HCl) and iron (Fe) can be represented by the equation:

Fe(s) + 2HCl(aq) → FeCl2(aq) + H2(g)

This reaction is a redox reaction, where iron is oxidized from an oxidation state of 0 in Fe to +2 in FeCl2, and hydrogen is reduced from +1 in HCl to 0 in H2.

The reason why ferrous chloride (FeCl2) is formed instead of ferric chloride (FeCl3) is due to the stoichiometry of the reaction. In this reaction, each iron atom reacts with two HCl molecules, which provide two chloride ions. This results in the formation of FeCl2, where the iron is in the +2 oxidation state (ferrous).

In order for ferric chloride (FeCl3) to form, each iron atom would need to react with three HCl molecules, which would provide three chloride ions. However, this would require a different reaction with different stoichiometry.

In addition, the formation of FeCl3 would require the iron to be oxidized to a +3 state, which requires more energy than oxidizing it to a +2 state. Therefore, under normal conditions, FeCl2 is the more likely product.