To determine the presence of anion and cation in the given salt
| Experiment | Observation | Inference |
|---|---|---|
| Take the salt and treat with concentrated H₂SO₄ | Colourless gas evolves and it etches glass | F⁻ may be present |
| Confirmatory Test | ||
| Calcium Chloride Test Treat salt solution with calcium chloride solution | White gelatinous precipitate forms | Presence of F⁻ is confirmed |
| Experiment | Observation | Inference |
|---|---|---|
| Confirmatory Test | ||
| If group-V is absent, add disodium hydrogen phosphate solution and scratch the inner walls with a glass rod | A white crystalline precipitate of magnesium ammonium phosphate is formed | Mg²⁺ is confirmed |
The given salt contains Mg²⁺ ions as cation and F⁻ ions as anion. The salt is Mg(F)₂.