What happens when iron reacts with dilute hydrochloric acid? Write observations and explanation for the products formed. Write the chemical reaction.
When dilute hydrochloric acid is added to iron hydrogen gas and iron(II)chloride are produced.
Observation:
Iron is said to displace hydrogen ions in solution producing fizzing colourless odourless hydrogen gas which pops near flame and iron(II)chloride are produced which is pale green is colour. If the solution is left to stand, the solution will turn pale brown, due to the oxidation of iron(II) ions (Fe2+) to iron(III) ions (Fe3+).
Equation:
Fe + 2HCl ====> FeCl2 + H2
Ferrous chloride (Pale green sol)
Solution left to stand
under goes oxidation
FeCl2 ------------------------------> FeCl3
Ferrous chloride Ferric chloride
(Pale green sol) (brown sol.)