Answer:
silver nitrate test
Step-by-step explanation:
The silver nitrate test is helps to detect fairly small concentrations of halide ions. The mixture is acidified by adding dilute nitric acid. This prevents unreacted hydroxide ions reacting with the silver ions. Then silver nitrate solution is added and silver halide is precipitated. A white precipitate forms from silver chlorine, cream from silver bromide and pale yellow for silver iodide.