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 |
|---|---|---|
| Confirmatory Tests | ||
| If no earlier anion test is positive, acidify the extract with dilute HCl and add BaCl₂ solution | White precipitate of barium sulphate, insoluble in conc. HCl or conc. HNO₃ is obtained | SO₄²⁻ may be present |
| Lead Acetate Test Acidify the solution with acetic acid and add lead acetate solution | White precipitate appears | Presence of SO₄²⁻ 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 SO₄²⁻ as the anion (acidic radical). The salt is Arsenic(III) Sulfate (As₂(SO₄)₃).