In the pigments, it is usually the type of metal that makes them coloured. Name the metal present in the 2 pigments you have made. Explain why does this metal make the compound coloured.
malachite Synthesis: 2CuSO₄ 5H₂O(aq) + 2Na₂CO₃(aq) -> CuCO₃ Cu(OH)2(s) + 2Na₂SO₄(aq) + CO₂(g) + 9H₂O(l)
Synthesis of Verdigris:
CuSO₄ 5H₂O(aq) + 4NH₃(aq) -> [Cu(NH₃)4]SO₄(aq) + 5H₂O(l)
[Cu(NH₃)4]SO₄(aq) + 2NaOH(aq) -> Cu(OH)2(s) + Na₂SO₄(aq) + 4NH₃(aq)
Cu(OH)2 + 2CH₃COOH(l) -> Cu(CH₃COO)2(s) + 2H₂O(l)