Qualitative reaction to halide ions

Presence of halide ions causes the formation of curdy precipitates.

Scientific name: Qualitative reaction on halide ions with silver nitrate is demonstrated.

YouTube

Testing for Halide ions

by Chris Lawrence

Testing for aqueous halide ions

by MaChemGuy

Качественные реакции на хлорид-, бромид- и йодид-ионы

by MrVella777

ELEMENTS FROM THE SEA: Reaction of Halide Ions with Silver Nitrate Solution

by Chemistry QMC

Testing For Halide Ions

by BluecoatChemistry

Qualitative Test for Chloride Ions in Aqueous Solution with Silver Nitrate (5%)

by Manofohm Chemical Creations

Halides in solution: Test using acidified silver nitrate and ammonia. From 20to9.com

by FranklyChemistry

Safety

Wear eye protection goggles and gloves.

Always follow general safety recommendations. Please note that conducting chemistry experiments you must comply with the relevant legal procedures in your country.

Reaction formula

NaCl + AgNO3 → AgCl + NaNO3 (white precipitate)

NaBr + AgNO3 → AgBr + NaNO3 (pale yellow precipitate)

KI + AgNO3 → AgI+ KNO3 (yellow precipitate)

Step-by-step instruction

  1. Prepare a solution which you want to test on presence of halide ions. For demonstration take solutions of potassium iodide, sodium bromide and sodium chloride.
  2. Pour solutions to the test tubes.
  3. Add a few drops of silver nitrate solution. If the solution under study contains halide ions the formation of a soft curdy precipitate is observed. The precipitate color is specific to the type of ion (chloride, bromide or iodide ion).

Scientific background

Qualitative analysis is the determination of the presence of an element in the compounds and mixtures without estimation of its amount. Qualitative reactions are one of the most common tools of qualitative analysis. If the sample under study contains ions specific to the qualitative reaction the release of gas bubbles or precipitate formation or color change is expected. This experiment demonstrates the way to detect halide ions. Potassium iodide, sodium bromide and sodium chloride solutions are used for demonstration. The reaction with silver nitrate is a qualitative reaction to chloride, bromide and iodide ions. It forms soft curdy precipitates of different color with solutions containing halide ions.

NaCl + AgNO3 → AgCl + NaNO3 (white precipitate)

NaBr + AgNO3 → AgBr + NaNO3 (pale yellow precipitate)

KI + AgNO3 → AgI+ KNO3 (yellow precipitate)

Danger:
Coolness:
Difficulty:

Published on 16 April 2015

  • Fire
  • Heating with fire
  • Explosion
  • Poisoned gas
  • Organic
  • Electricity
  • Solution
  • Oxidation reduction
  • Color change
  • Precipitate
  • Gassing
  • Catalyst