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Can someone explain why this happens [displacement of halides reaction]? watch

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    Experiment:
    Add a few drops of chlorine solution to an equal volume of potassium bromide solution.
    Shake the tube and record the appearance of its contents.
    Add a few drops of cyclohexane to this tube.
    Shake the tube again and record the appearance of its contents

    Observation:
    addition of chlorine solution results in a yellow solution
    addition of cyclohexane produces two layers.
    upper layer is brown/orange
    lower layer is light yellow

    Can someone explain why addition of chlorine solution makes a yellow solution and why the layers are the colours they are?

    Thanks
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    (Original post by faiqah)
    Experiment:
    Add a few drops of chlorine solution to an equal volume of potassium bromide solution.
    Shake the tube and record the appearance of its contents.
    Add a few drops of cyclohexane to this tube.
    Shake the tube again and record the appearance of its contents

    Observation:
    addition of chlorine solution results in a yellow solution
    addition of cyclohexane produces two layers.
    upper layer is brown/orange
    lower layer is light yellow

    Can someone explain why addition of chlorine solution makes a yellow solution and why the layers are the colours they are?

    Thanks
    Potassium bromide solution is colourless.

    chlorine solution (at moderate to high concentration) is yellow or greenish yellow.

    When you add the two, chlorine oxidises the bromide ion to bromine (which is orange/brown) as chlorine is more reactive than bromine. The bromine produced dissolves in the cyclohexane to form a brown solution.

    Cl_2 + 2Br^- \rightarrow Br_2 + 2Cl^-
 
 
 
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