Anion tests

Carbonate or Hydrogencarbonate Test observation

Effervescence/fizzing. Gas given off by both turns limewater milky. White precipitate forms if carbonate. No precipitate if hydrogencarbonate

Nitrate test

Brown ring test. Add FeSO4 to solution. Drop concentrated sulfuric acid down the side of the test tube

Nitrate test observation

Brown ring formed at junction. Nitrate anion is present

Phosphate test

Add ammonia molybdate to a solution. Add concentrated nitric acid. Warm the Solution

Phosphate test observation

Yellow precipitate is formed. Phosphate anion is present

Chloride test

Add chlorine salt. Add drops of silver nitrate. Solution is clear. Add quarter test tube of dilute ammonia

Chloride test Observation

Test tube goes milky (precipitate) goes back to being colourless

Sulfate test

Fill two test tube to a quarter with deionised water. Add sulfate salt to one. Add sulfite to the other. Add barium chloride to both. Add dilute hydrochloric acid to both

Sulfate test observation

Both form precipitate, when hydrochloric acid is added to sulphite solution it turns colourless.

Carbonate or Hydrogencarbonate Test

Place carbonate salt in boiling tube. Add dilute hydrochloric acid. Bubble gas through limewater. Repeat previous steps with hydrogencarbonate salt. Add magnesium sulfate

Chloride test equation

Ag⁺ + Cl^- → AgCl↓

Sulphate test equation

Ba²⁺ + SO4^2-→ BaSO4↓

Sulphite test equation

Ba²⁺ + SO3^2- → BaSO3↓

Carbonate test equation (HCl)

CO3^2- + 2H⁺ → CO2 + H2O

Hydrogencarbonate test equation (HCl)

HCO3^- + H⁺ → CO2 + H2O

Hydrogencarbonate/carbonate (carbon dioxide/limewater)

Ca(OH)2 + CO2 → CaCO3↓ + H2O

Carbonate test equation (MgSO4)

Mg²⁺ + CO3^2- → MgCO3↓

Hydrogencarbonate test equation (MgSO4)

Mg²+ + 2HCO3^- → Mg(HCO3)2

What does ↓ mean in a chemical equation?

A precipitate is formed