======Halogen Displacement======


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**Safety: **{{$demo.safety_description}}\\
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**Alternative titles:** Halogen Reactivity Series
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====Summary====                   
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====Procedure====  
  - Place a few drops of each potassium halide salt solution (KCl, KBr, KI) into separate wells on a spotting tile.  
  - Add a few drops of chlorine water to each well and observe any changes.  
  - Repeat the process using bromine water and iodine water, testing each halogen solution against all three halide salts.  
  - Look for color changes, precipitate formation, or fading of color (distinguishing real reactions from dilution).  
  - Test the pH of each well with universal indicator paper.  
  - Compare results to determine which halogen has displaced another.



====Links==== 
Halogen Displacement Reactions - Royal Society of Chemistry: 
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Displacement of Halogens - Rugby School Chemistry: 
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📄 Halogen Displacement - Practical Science: [[https://practical-science.com/2023/04/08/halogen-displacement/]]\\


====Variations====
  * Record the intensity of color changes using a color chart for more precise comparisons.  
  * Extend the experiment with sodium halide salts to confirm consistency across different cations.  
  * Use cyclohexane as an organic solvent to extract displaced halogens (especially iodine and bromine) for clearer visualization.



====Safety Precautions====
  * Wear safety goggles and a lab coat at all times.  
  * Handle chlorine, bromine, and iodine solutions with care; they can be irritants or toxic.  
  * Perform the experiment in a well-ventilated area or fume hood.  
  * Avoid direct contact with chemicals; use droppers and gloves.  
  * Dispose of waste solutions properly according to school or local safety guidelines.




====Questions to Consider====
  * Which halogens displaced others in the reactions? (Chlorine displaces bromide and iodide; bromine displaces iodide; iodine does not displace others.)  
  * How does this experiment support the halogen reactivity series? (Reactivity decreases down Group 17: Cl₂ > Br₂ > I₂.)  
  * Why might color changes be more visible in certain reactions? (Different halogens form solutions with distinctive colors, e.g., iodine brown, bromine orange.)  
  * How does this experiment demonstrate oxidation and reduction? (The more reactive halogen is reduced to halide ions, while the less reactive halide is oxidized to elemental halogen.)