Answer to Question #129260 in General Chemistry for A

Question

Hi,

When iron(III) sulfate solution is added to sodium carbonate solution, it fizzes and forms a brown precipitate. This is because:
the aqueous iron(III) ion is acidic and forms iron hydroxide and hydrogen.
the aqueous iron(III) ion is acidic and forms iron carbonate and carbon dioxide.
the aqueous iron(III) ion is acidic and forms iron hydroxide and carbon dioxide.
the aqueous iron(III) ion is acidic and forms iron carbonate and hydrogen.

Answer 1

Because of the acidic character of aqueous Fe³⁺ ion, iron (III) hydroxide will be formed instead of iron (III) carbonate due to the displacement of CO₂:

Fe₂(SO₄)₃ + 3Na₂CO₃ + 3H₂O --> 2Fe(OH)₃ + 3Na₂SO₄ + 3CO₂

Answer: the aqueous iron(III) ion is acidic and forms iron hydroxide and carbon dioxide.