Cambridge O Level Chemistry · Syllabus 5070 · Experimental Techniques and Chemical Analysis
Anion Test
What is Anion Test?
A chemical test that identifies a negatively charged ion in a sample. Seven are required: carbonate by adding dilute acid and testing the gas for carbon dioxide; chloride, bromide and iodide by acidifying with dilute nitric acid then adding aqueous silver nitrate, giving white, cream and yellow precipitates respectively; nitrate by adding aqueous sodium hydroxide then aluminium foil and warming carefully, giving ammonia; sulfate by acidifying with dilute nitric acid then adding aqueous barium nitrate, giving a white precipitate; and sulfite by adding a small volume of acidified aqueous potassium manganate(VII), which changes from purple to colourless.
This definition is part of the Experimental Techniques and Chemical Analysis chapter in Cambridge O Level Chemistry.