[KBenson]

I'm revising for my A2 summer exam for OCR chemistry (F325) and i'm looking at the variable oxidation states for transition metals... I remember my teachers saying we don't need to know all of the colour changes. I think they said we need to know the Vanadium ones, but I can't remember the others?

Does anyone have any ideas which ones we need to know?

Thank you!

[Cottrill]

Hexaaqua Copper (II) ion [Cu(H₂O)₆]²⁺_(aq) is blue.

Tetraamine diaqua Copper (II) ion [Cu(NH₄)₄(H₂O)₂]²⁺_(aq) is deep blue.

Tetrachlorocuprate ion [CuCl₄]^2-_(aq) is yellow (formed by reacting Hexaaqua Copper (II) ions with conc. HCl, it's an equilibrium rxn so it changes colour from blue to green to yellow.)

Hexaaqua Cobalt (II) ion [CO(H₂O)₆]²⁺_(aq) is pink.

Tetrachlorocobaltate ion [CoCl₄]^2-_(aq) is blue.

I don't think you need to know the colours of any other TM ions.

[KBenson]

(Original post by Cottrill)
Hexaaqua Copper (II) ion [Cu(H₂O)₆]²⁺_(aq) is blue.

Tetraamine diaqua Copper (II) ion [Cu(NH₄)₄(H₂O)₂]²⁺_(aq) is deep blue.

Tetrachlorocuprate ion [CuCl₄]^2-_(aq) is yellow (formed by reacting Hexaaqua Copper (II) ions with conc. HCl, it's an equilibrium rxn so it changes colour from blue to green to yellow.)

Hexaaqua Cobalt (II) ion [CO(H₂O)₆]²⁺_(aq) is pink.

Tetrachlorocobaltate ion [CoCl₄]^2-_(aq) is blue.

I don't think you need to know the colours of any other TM ions.

Thank you

[clownfish]

Just to add, take a look at the syllabus when you are unsure of this kind of thing as it will tell you on there.