In qualitative analysis and inorganic chemistry, various reactions are used to identify transition metals, Group 2 cations, and halide anions. Which ionic equation represents a precipitation reaction?
[Cu(H2O)6]2+(aq)+4Cl−(aq)⟶[CuCl4]2−(aq)+6H2O(l)\text{[Cu(H}_2\text{O)}_6\text{]}^{2+}(aq) + 4\text{Cl}^-(aq) \longrightarrow \text{[CuCl}_4\text{]}^{2-}(aq) + 6\text{H}_2\text{O}(l)[Cu(H2O)6]2+(aq)+4Cl−(aq)⟶[CuCl4]2−(aq)+6H2O(l)
Cl2(aq)+2I−(aq)⟶2Cl−(aq)+I2(aq)\text{Cl}_2(aq) + 2\text{I}^-(aq) \longrightarrow 2\text{Cl}^-(aq) + \text{I}_2(aq)Cl2(aq)+2I−(aq)⟶2Cl−(aq)+I2(aq)
Ba2+(aq)+SO42−(aq)⟶BaSO4(s)\text{Ba}^{2+}(aq) + \text{SO}_4^{2-}(aq) \longrightarrow \text{BaSO}_4(s)Ba2+(aq)+SO42−(aq)⟶BaSO4(s)
NH4+(aq)+OH−(aq)⟶NH3(g)+H2O(l)\text{NH}_4^+(aq) + \text{OH}^-(aq) \longrightarrow \text{NH}_3(g) + \text{H}_2\text{O}(l)NH4+(aq)+OH−(aq)⟶NH3(g)+H2O(l)
55 exam-style questions on OCR GCSE Chemistry Types of chemical reactions. Each one has a worked solution and a mark scheme showing where the marks go.