What happens when dilute HCl is poured on a mixture of iron and sulphur.
If we will take a mixture of Fe and sulfur and add Dilute HCl only iron will react to form FeCl2, reaction will takes place as follows
Fe + 2HCl → FeCl2 + H2 .
But if the mixture of Fe and S is heated they form FeS. If we add HCl in FeS it will release H2S. Reaction takes place as follows:
FeS + 2HCl → FeCl2 + H2S