Detecting Anions Flashcards
How do you detect carbonate ions?
Add the metal carbonate to a dilute acid, and effervescence will be observed. The gas can be verified as carbon dioxide by bubbling it through limewater, and seeing if it turns cloudy white. This will show that carbonate ions are present as carbon dioxide is a product of the acid-carbonate reaction.
How do you detect Sulfate ions?
Add dilute hydrochloric acid to remove carbonate ions, and then add barium chloride solution. If a white precipitate forms, sulfate ions are present.
How do you detect halide ions?
Add dilute nitric acid, and then silver nitrate. If a precipitate forms, a halide ion is present. Chloride: White precipitate, Bromide: Cream precipitate, Iodide: Yellow precipitate.
What is the downside to the halide test?
The chloride and bromide precipitates look very similar.
