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Water - Solubility - Ions

Negative Ions - Bromide, Chloride and Iodide.

The Silver Nitrate Test for Bromide, Chloride and Iodide Ions.
The test will give a white precipitate of silver chloride,
a cream (off white) precipitate of silver bromide
and a yellow precipitate of silver iodide.

silver nitrate   +  sodium chloride silver chloride  +  sodium nitrate.
AgNO_3(aq)       +        NaCl_(aq)               AgCl_(s)      +     NaNO_3(aq)

The ionic equation is    Ag⁺_(aq)  +  Cl^-_(aq)    AgCl_(s)
Silver chloride is white.

silver nitrate   +  lithium bromide silver bromide  +  lithium nitrate.
AgNO_3(aq)       +        LiBr_(aq)               AgBr_(s)      +     LiNO_3(aq)

The ionic equation is    Ag⁺_(aq)  +  Br^-_(aq)    AgBr_(s)
Silver bromide is cream.

silver nitrate   +  potassium iodide silver iodide  +  potassium nitrate.
AgNO_3(aq)       +        KI_(aq)               AgI_(s)      +     KNO_3(aq)

The ionic equation is    Ag⁺_(aq)  +  I^-_(aq)    AgI_(s)
Silver iodide is yellow.

The tests above are made in the presence of dilute nitric acid
to remove any carbonate or sulfite ions which may be present.
These ions will also produce a precipitate which would confuse the results.

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