Qualitative analysis
How to do salt analysis · Viva · Quiz
To analyse the given inorganic salt for one acidic and one basic radical.
| Experiment | Observation | Inference |
|---|---|---|
| Take 0.1 g salt and add conc. H₂SO₄ | Colourless gases are evolved. On testing further, CO₂ and CO are evolved | C₂O₄²⁻ may be present |
| Confirmatory Tests | ||
| Calcium Chloride Test Acidify extract with acetic acid and add calcium chloride | White precipitate of calcium oxalate is obtained | C₂O₄²⁻ is confirmed |
| KMnO₄ Test Filter and add dilute H₂SO₄ to the precipitate, then dilute KMnO₄ and warm | KMnO₄ pink colour is discharged | C₂O₄²⁻ is confirmed |
| Experiment | Observation | Inference |
|---|---|---|
| Original solution + H₂S gas in presence of dil. HCl and NH₄Cl | Yellow precipitate is formed | Group-II-B (As³⁺) may be present |
| Confirmatory Test | ||
| Ammonium Molybdate Test Treat the dissolved precipitate with concentrated nitric acid and ammonium molybdate solution | Canary yellow precipitate is formed | Presence of As³⁺ is confirmed |
The given salt contains As³⁺ as the cation (basic radical) and C₂O₄²⁻ as the anion (acidic radical). The salt is Arsenic(III) Oxalate (As₂(C₂O₄)₃).