Testing for Halide Ions

Flashcards covering the identification tests for halide ions, including silver nitrate and ammonia reactions, solubility products, and concentrated sulphuric acid tests.

Dilute nitric acid (in halide testing)

Added to the solution before silver nitrate to react with and remove other ions that might give a confusing precipitate.

Silver Nitrate Solution

A reagent used to test for halide ions in solution, which must be acidified with dilute nitric acid beforehand.

Chloride ($Cl^-$) observation with silver nitrate

Forms a white precipitate of silver chloride ($AgCl$).

Bromide ($Br^-$) observation with silver nitrate

Forms a very pale cream precipitate of silver bromide ($AgBr$).

Iodide ($I^-$) observation with silver nitrate

Forms a very pale yellow precipitate of silver iodide ($AgI$).

Fluoride ($F^-$) result with silver nitrate

No precipitate is formed because silver fluoride is soluble.

Ammonia test for silver chloride ($AgCl$)

The precipitate dissolves in dilute ammonia solution to give a colourless solution.

Ammonia test for silver bromide ($AgBr$)

The precipitate is almost unchanged by dilute ammonia but dissolves in concentrated ammonia solution to give a colourless solution.

Ammonia test for silver iodide ($AgI$)

The precipitate is insoluble in ammonia solution of any concentration.

Concentrated sulphuric acid test for Fluoride ($F^-$) and Chloride ($Cl^-$)

Produces steamy acidic fumes of $HF$ or $HCl$ respectively.

Concentrated sulphuric acid test for Bromide ($Br^-$)

Produces steamy acidic fumes of $HBr$ contaminated with brown bromine vapour.

Concentrated sulphuric acid test for Iodide ($I^-$)

Produces some steamy fumes of $HI$, but lots of purple iodine vapour and various red colours in the tube.