Testing For Positive ions.
- Lithium: Crimson/Red
- Sodium: Orange/Yellow
- Pottasium: Lilac
- Calcium: Brick Red
- Barium: Green
Hydroxide of metal + Sodium Hydroxide:
(Aluminium or Calcium or Magnesium) + NaOH = White precipitate
Aluminium + excess NaOH, the precipitate dissolves.
- Copper (II) hydroxide = Blue precipitate
- Iron (II) hydroxide = Green precipitate
- Iron (III) hydroxide = Brown precipitate
Testing For Negative ions.
Carbonate ions: Add dilute Hydrochloric acid and see if it fizzes. If it does and the gas produced turns limewater cloudy, the substance contains carbonate ions.
Halide ions: Add dilute Nitric acid and then Slive NItrate solution.
- Chloride ions: White precipitate
- Bromide ions: Cream precipitate
- Iodide ions: Yellow precipitate
Sulfate ions: Add dilute Hydrochloric acid and the Barium CHloride solution. Form white precipitate.