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 |
|---|---|---|
| Universal Indicator | Solution turns blue or purple | OH⁻ may be present |
| Confirmatory Test | ||
| Phenolphthalein Test Add phenolphthalein indicator to salt solution | Solution turns pink | OH⁻ is confirmed |
| Experiment | Observation | Inference |
|---|---|---|
| Original solution + H₂S gas in presence of NH₄OH | Black precipitate is formed | Group IV cation may be present |
| Dissolve black precipitate in aqua regia | Nickel chloride solution is obtained | Ni²⁺ may be present |
| Confirmatory Test | ||
| Dimethylglyoxime Test Make the solution alkaline with NH₄OH and add dimethylglyoxime | Brilliant red precipitate | Presence of Ni²⁺ is confirmed |
The given salt contains Ni²⁺ as the cation (basic radical) and OH⁻ as the anion (acidic radical). The salt is Nickel(II) Hydroxide (Ni(OH)₂).