To determine the presence of anion and cation in the given salt
| 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 |
|---|---|---|
| Salt solution + NaOH solution | Dirty green precipitate | Fe²⁺ may be present |
| Confirmatory Test | ||
| Potassium Ferricyanide Test Add potassium ferricyanide solution | Dark blue precipitate (Turnbull's blue) | Presence of Fe²⁺ is confirmed |
The given salt contains Fe²⁺ ions as cation and C₂O₄²⁻ ions as anion. The salt is FeC₂O₄.