OCR A Level Chemistry - Transition Metals - Precipitation and Ligand Substitution

Cu²⁺ in water

Blue solution

Cu²⁺ in NaOH(aq)

Blue precipitate

Cu²⁺ in excess NaOH(aq)

No change

Cu²⁺ in excess NH₃(aq)

Precipitate dissolves, dark blue solution

Cu²⁺ in NH₃(aq)

Blue precipitate

Cu²⁺ in concentrated HCl

Yellow Solution

Fe²⁺ in water

Pale green solution

Fe²⁺ in NaOH(aq)

Dark green precipitate

Fe²⁺ in excess NaOH(aq)

No change

Fe²⁺ in NH₃(aq)

Brown precipitate

Fe²⁺ in excess NH₃(aq)

No change

Fe²⁺ in concentrated HCl

No reaction

Fe³⁺ in water

Yellow solution

Fe³⁺ in NaOH(aq)

Green precipitate

Fe³⁺ in excess NaOH(aq)

No change

Fe³⁺ in NH₃(aq)

Orange-brown precipitate

Fe³⁺ in excess NH₃(aq)

No change

Fe³⁺ in concentrated HCl

No reaction

Mn²⁺ in water

Pale pink solution

Mn²⁺ in NaOH(aq)

Light brown solution

Mn²⁺ in excess NaOH(aq)

No change

Mn²⁺ in NH₃(aq)

Light brown precipitate

Mn²⁺ in excess NH₃(aq)

No change

Mn²⁺ in concentrated HCl

No reaction

Cr³⁺ in water

Green solution

Cr³⁺ in NaOH(aq)

Green precipitate

Cr³⁺ in excess NaOH(aq)

Precipitate dissolves, green solution

Cr³⁺ in NH₃(aq)

Green precipitate

Cr³⁺ in excess NH₃(aq)

Precipitate dissolves, purple solution

Cr³⁺ in concentrated HCl

No reaction