Carrying out test tube reactions to identify cations and anions in solution

Cation/Anion Reagent Result
Ammonium NaOH, gently heat, hold damp red litmus over Production of ammonia gas, litmus turns blue
Carbonate HCl, test gas with calcium hydroxide solution (limewater) Effervescence, CO2 gas produced, limewater turns cloudy
Sulfate HCl then barium chloride Production of white precipitate
Chloride (aq) Nitric acid, then silver nitrate

Add dilute ammonia solution

Production of white precipitate

Precipitate dissolves

Chloride (solid) Add concentrated H2SO4 Production of steamy fumes of HCl

 

Bromide (aq) Nitric acid, then silver nitrate

Add concentrated ammonia solution

Production of cream precipitate

Precipitate dissolves

Bromide (solid) Add concentrated H2SO4 Production of steamy fumes of HBr, and red/brown Br2
Iodide (aq) Nitric acid, then silver nitrate

Add concentrated ammonia solution

Production of pale yellow precipitate

No visible change

Iodide (solid) Add concentrated H2SO4 Production of steamy fumes of HI, H2S (smells of rotten eggs, black solid iodine, and sometimes yellow solid sulfur

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