Transition Metals- Reactions of aqua ions

Notes from Chemsheets ppt= precipitate NFR= no further reaction

[Fe(H2O)₆]²⁺

[Fe(H2O)₆]²⁺

green solution

[Cu(H2O)₆]²⁺

blue solution

[Fe(H2O)6]3+

orange solution due to hydrolysis to [Fe(H2O)5(OH)]2+

[Al(H2O)6]3+

colourless solution

[Fe(H2O)6]2+ and NaOH

[Fe(H2O)4(OH)2]

(dark) green ppt

XS: NFR

[Cu(H2O)6]2+ and NaOH

[Cu(H2O)4(OH)2]

blue ppt

XS: NFR

[Fe(H2O)6]3+ and NaOH

[Fe(H2O)3(OH)3]

brown ppt

XS: NFR

[Al(H2O)6]3+ and NaOH

[Al(H2O)3(OH)3]

white ppt

XS: NFR

[Fe(H2O)6]2+ and NH3

[Fe(H2O)4(OH)2]

(dark) green ppt

XS: NFR

[Cu(H2O)6]2+ and NH3

[Cu(H2O)₄(OH)₂]

blue ppt

XS: [Cu(H2O)₂(NH3)₄]²⁺

deep blue solution

[Fe(H2O)6]3+ and NH3

[Fe(H2O)3(OH)3]

brown ppt

XS: NFR

[Al(H2O)6]3+ and NH3

[Al(H2O)3(OH)3]

white ppt

NFR

[Fe(H2O)6]2+ and Na2CO3

FeCO3

green ppt

[Cu(H2O)6]2+ and Na2CO3

CuCO3

blue-green ppt

[Fe(H2O)6]3+ and Na2CO3

[Fe(H2O)3(OH)3]

brown ppt + CO2 bubbles

[Al(H2O)6]3+ and Na2CO3

[Al(H2O)3(OH)3]

white ppt + CO2 bubbles

[Fe(H2O)6]2+ and conc. HCl

[FeCl4]2-

yellow solution

[Cu(H2O)6]2+ and conc. HCl

[CuCl4]2-

green solution

[Fe(H2O)6]3+ and conc. HCl

[FeCl4]-

yellow solution

[Al(H2O)6]3+ + HCl

[AlCl4]-

colourless solution

If you add HCl to the [Cu(H2O)4(OH)2] formed CuSO4 + NaOH, why does the precipitate redissolve?

H+ will react with OH- from complex ion. [OH-] decreases, so equilibrium shifts to LHS to increase OH- formed and ppt redissolves.