What colour are aqueous Fe²⁺ ions? [Fe(H₂O)₆]²⁺
Pale Green
Green
Blue
Brown
What colour are aqueous Fe²+ ions in a small amount of OH- [Fe(H₂O)₆]²⁺ + 2OH- → Fe(H₂O)₄(OH)₂ (s) + 2H₂O
Green glatinous precipitate
Green precipitate
Brown gelatinous precipitate
Yellow
What colour are aqueous Fe²+ ions in a small amount of NH₃ [Fe(H₂O)₆]²⁺ + 2NH₃ → Fe(H₂O)₄(OH)₂ (s) + 2NH₄⁺
Green Gelatinous precipitate
Brown Gelatinous Preciptate
Blue Gelatinous
What colour are aqueous Fe²+ ions when OH- is added in excess [Fe(H₂O)₆]²⁺ + 2OH- → Fe(H₂O)₄(OH)₂ (s) + 2H₂O
Green Gelatinous Precipitate
Yellow Gelatinous Precipitae
Purple
Brown Gelatinous Precipitate
What colour are aqueous Fe²+ ions when NH₃ is added in excess [Fe(H₂O)₆]²⁺ + 2NH₃ → Fe(H₂O)₄(OH)₂ (s) + 2NH₄⁺
Green gelationuos precipitate
Brown precipitate
Blue Gelatinous Precipitate
Yellow Precipitate
Why does Fe(H₂O)₄(OH)₂ (s) turn brown in air?
Oxidised by oxygen in air
Fe(H₂O)₃(OH)₃ is formed which is Brown
It is reduced by air
There are impurities
What is formed when Fe²⁺ is added to CO₃²⁻ ? And what colour is it?
FeCO₃ Iron Carbonate
Green gelatinous precipitate
Fe₂(CO₂)₃
What colour is aqueous Co²⁺ ? And what is its formula?
[Co(H₂O)₆]²⁺
Pink
Co(H₂O)₄(OH)₂
What colour are aqueous Co²+ ions in a small amount of OH- [Co(H₂O)₆]²⁺ + 2OH- → Co(H₂O)₄(OH)₂ (s) + 2H₂O
Blue Precipitate
Pink Precipitae
What colour are aqueous Co²+ ions in a small amount of NH₃ [Co(H₂O)₆]²⁺ + 2NH₃ → Co(H₂O)₄(OH)₂ (s) + 2NH₄⁺
Orange
Pale Blue Precipitate
What colour are aqueous Co²+ ions when OH- is added in excess? [Co(H₂O)₆]²⁺ + 2OH- → Co(H₂O)₄(OH)₂ (s) + 2H₂O
Blue gelatinous precipitate
What colour are aqueous Co²+ ions when NH₃ is added in excess? What is the formula? [Co(H₂O)₆]²⁺ + 2NH₃ →
Co(NH₃)₆
Pale Yellow
Why does [Co(NH₃)₆]²⁺ turn to a brown solution in air?
Co²⁺ is oxidied by air to form Co³⁺
Ligand Exchange takes place
What is fromed when Co²+ ions are in the presence of CO₃²⁻ ? And what colour is it? [Co(H₂O)₆]²⁺ + CO₃²⁻ →
t is formed
[Co(H₂O)₆]²⁺ + OH- → Co(H₂O)₄(OH)₂ (s) + 2H₂O
CoCO₃
Pink Precipitate
Blue precipitate
Co(H₂O)₄(CO₃)₂
What colour are aqueous Cu²+ ions [Cu(H₂O)₆]²⁺
Pale Blue
What colour are aqueous Cu²+ ions in a small amount of OH- [Cu(H₂O)₆]²⁺ + 2OH- → Cu(H₂O)₄(OH)₂ (s) + 2H₂O
Deep Blue precipitate
Green Precipitate
Orange precipitate
What colour are aqueous Cu²+ ions OH- are added in excess? [Cu(H₂O)₆]²⁺ + 2OH- → Cu(H₂O)₄(OH)₂ (s) + 2H₂O
Pale blue precipitate
Dark Blue solution
Pale Blue Solution
What colour are aqueous Cu²+ ions in a small amount of NH₃ [Cu(H₂O)₆]²⁺ + 2NH₃ → Cu(H₂O)₄(OH)₂ (s) + 2NH₄⁺
Pale Blue solution
Pale Blue precipitate
Colourless Solution
Yellow precipitate
What colour are aqueous Cu²+ when NH₃ is added in excess [Cu(H₂O)₆]²⁺ + 4NH₃ → [Cu(NH₃)₄(H₂O)₂]²⁺ + 4H₂O
Deep Blue Solution
Deep Blue Precipitate
What colour are aqueous Cu²+ when in the presence of CO₃²⁻ [Cu(H₂O)₆]²⁺ + 2CO₃²⁻ → CuCO₃ (s) + 6H₂O
Blue-Green Solution
Blue-Green Precipitate
Red Precipitate
What colour are aqueous Fe³⁺ ?
What colour are aqueous Fe³⁺ ions in a small amount of OH-? [Fe(H₂O)₆]³⁺ + 3OH- → Fe(H₂O)₃(OH)₃ (s) + 3H₂O
Brown Precipitate
What colour are aqueous Fe³⁺ ions when OH- is added in excess? [Fe(H₂O)₆]³⁺ + 3OH- → Fe(H₂O)₃(OH)₃ (s) + 3H₂O
Brown Solution
Yellow Solution
What colour are aqueous Fe³⁺ ions in a small amount of NH₃ [Fe(H₂O)₆]³⁺ + 3NH₃ → Fe(H₂O)₃(OH)₃ (s) + 3NH₄⁺
Green Solution
Blue Solution
What colour are aqueous Fe³⁺ ions when NH₃ is added in excess? [Fe(H₂O)₆]³⁺ + 3NH₃ → Fe(H₂O)₃(OH)₃ (s) + 3NH₄⁺
Yellow Gelatinous Precipitate
What is observed when aqueous Fe³⁺ ions when in the presence of CO₃²⁻? What is formed? [Fe(H₂O)₆]³⁺ + 3CO₃²⁻ →
Fe(H₂O)₃(OH)₃ + CO₂
Brown Gelatinous precipitate Effervesence (Bubbles)
Fe(H₂O)₄(OH)₂ + CO₂
Green Gelatinous Precipitate Effervesence (Bubbles)
What colour are aqueous Al³⁺ ions in a small amount of OH- [Al(H₂O)₆]³⁺ + 3OH- → Al(H₂O)₃(OH)₃ (s) + 3H₂O
Colourless
White precipitate
Pink Solution
What colour are aqueous Al³⁺ ions [Al(H₂O)₆]³⁺
Colourless solution
Red Solution
Silver solution
What colour are aqueous Al³⁺ ions when OH- is added in excess? [Al(H₂O)₆]³⁺ + 4OH- → [Al(OH)₄]⁻ (s) + 6H₂O
Red precipitate
Red solution
White Solution
What colour are aqueous Al³⁺ ions in a small amount of NH₃ [Al(H₂O)₆]³⁺ + 3NH₃ → Al(H₂O)₃(OH)₃ (s) + 3NH₄⁺
White Precipitate
Orange Precipitate
What colour are aqueous Al³⁺ ions when NH₃ is added in excess [Al(H₂O)₆]³⁺ + 3NH₃ → Al(H₂O)₃(OH)₃ (s) + 3NH₄⁺
White solution
What is observed when Al³⁺ are in the presence of CO₃²⁻ ? What is produced? [Al(H₂O)₆]³⁺ + CO₃²⁻ → Al(⁻H₂O)₃(OH)₃ (s) + 3H₂O
Al(⁻H₂O)₃(OH)₃ (s) + CO₂
White Precipitate Effervesence (Bubbles)
Al(H₂O)₄(OH)₂ + CO₂
Colourless Solution Effervesence
What colour are aqueous Cr³⁺ ions? [Cr(H₂O)₆]³⁺
Ruby
What colour are aqueous Cr³⁺ ions in a small amount of OH- [Cr(H₂O)₆]³⁺ + 3OH- → Cr(H₂O)₃(OH)₃ (s) + 3H₂O
What colour are aqueous Cr³⁺ when OH- is added in excess? [Cr(H₂O)₆]³⁺ + 6OH- → [Cr(OH)₆]³⁻ (s) + 6H₂O
What colour are aqueous Cr³⁺ ions in a small amount of NH₃ [Cr(H₂O)₆]³⁺ + 3NH₃ → Cr(H₂O)₃(OH)₃ (s) + 3NH₄⁺
What colour are aqueous Cr³⁺ ions when NH₃ is added in excess? [Cr(H₂O)₆]³⁺ + 3NH₃ → [Cr(NH₃)₆]³⁺ (s) + 6H₂O
Purple Solution
Purple Precipitate
What is observed when Cr³⁺ ions are in the presence of CO₃²⁻ ? What is formed? [Cr(H₂O)₆]³⁺ + 3CO₃²⁻ →
Cr(H₂O)₃(OH)₃ (s) + CO₂
Green Precipitate Effervesence (Bubbles)
Cr(H₂O)₄(OH)₂ (s) + CO₂
Green Solution Effervesence (Bubbles)
