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====Halides====
The test for [[Halide]] [[anion]]s begins by adding dilute [[Nitric Acid]] to remove any possible [[Carbonate]]s. Then [[Silver Nitrate]] is added to form a [[precipitate]] of [[Silver Halide]].
<chemmath>NaCl(aq) + AgNO3AgNO_3(aq) -> NaNO3→ NaNO_3(aq) + AgCl(s)</chemmath>
: A white [[precipitate]] is formed.
<chemmath>NaBr(aq) + AgNO3AgNO_3(aq) -> → NaNO3(aq) + AgBr(s)</chemmath>
: A cream coloured [[precipitate]] is formed.
<chemmath>NaI(aq) + AgNO3AgNO_3(aq) -> → NaNO3(aq) + AgI(s)</chemmath>
: A yellow [[precipitate]] is formed.
====Sulphates====
The test for [[Sulphate]] [[anion]]s begins by adding dilute [[Hydrochloric Acid]] to remove any possible [[Carbonate]]s. Then [[Barium Chloride]] is added to form a [[precipitate]] of [[Barium Sulphate]].
<chemmath>Na2SO4Na_2SO_4(aq) + BaCl2BaCl_2(aq) -> → 2NaCl(aq) + BaSO4BaSO_4(s)</chemmath>
: A white [[precipitate]] is formed.
====Carbonates====
The test for [[carbonate]] [[anion]]s begins by adding [[Hydrochloric Acid]] to the [[solution]]. This [[product|produces]] a [[gas]] which is collected and bubbled through [[Limewater]] to identify if [[Carbon Dioxide]] has been [[product|produced]]. If [[Carbon Dioxide]] has been [[product|produced]] then the [[Limewater]] will turn from [[transparent]] to cloudy.
<chemmath>Na2CO3Na_2CO_3(aq) + 2HCl(aq) -> → 2NaCl(aq) + H2OH_2O(l) + CO2CO_2(g)</chemmath>
: A [[gas]] is [[product|produced]] and bubbled through [[Limewater]].
<chemmath>CO2CO_2(g) + CaO(aq) -> CaCO3→ CaCO_3(s)</chemmath>
: The [[Calcium Carbonate]] makes the [[Limewater]] appear cloudy.