Transition metals Iron reactions

Question 1

[Fe(H2O)6]2+ +2OH- aqueous NaOH
Colour change?
Acid base or ligand substitution?

Answer 1

[Fe(OH)2(H2O)4] + 2H2O

Pale blue solution to green precipitate

Question 2

[Fe(H2O)6]2+ +2NH3 aqueous ammonia
Colour change?
Acid base or ligand substitution?

Answer 2

[Fe(OH)2(H2O)4] + 2NH4+

Pale blue solution to green precipitate

Question 3

Upon standing what happens to [Fe(OH)2(H2O)4]

Colour change?

Answer 3

[Fe(OH)3(H20)3]
Oxidation by O2
From green precipitate to orange/brown precipitate

Question 4

[Fe(H2O)6]3+ +3OH- aqueous NaOH

Colour change?

Answer 4

[Fe(OH)3(H20)3] + 3H2O

Yellow solution to orange brown ppt

Question 5

[Fe(H2O)6]3+ +3NH3 aqueous NaOH

Colour change?

Answer 5

[Fe(OH)3(H20)3] + 3NH4+

Yellow solution to orange brown ppt

Question 6

For both solutions containing the complex ions Fe2+ and Fe3+, what happens on the addition of excess aq NaOH or aq NH3

Answer 6

No further reactions.