Presence of halide ions causes the formation of curdy precipitates.
name: Qualitative reaction on halide ions with silver nitrate is demonstrated.
Qualitative analysis is the determination of the presence of an element in the compounds and mixtures without estimation of its amount. Qualitative reactions are one of the most common tools of qualitative analysis. If the sample under study contains ions specific to the qualitative reaction the release of gas bubbles or precipitate formation or color change is expected. This experiment demonstrates the way to detect halide ions. Potassium iodide, sodium bromide and sodium chloride solutions are used for demonstration. The reaction with silver nitrate is a qualitative reaction to chloride, bromide and iodide ions. It forms soft curdy precipitates of different color with solutions containing halide ions.
NaCl + AgNO3 → AgCl + NaNO3 (white precipitate)
NaBr + AgNO3 → AgBr + NaNO3 (pale yellow precipitate)
KI + AgNO3 → AgI+ KNO3 (yellow precipitate)