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Litmus paper tests watch

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    Could anybody pls help me out with litmus paper tests... Such as what sort of paper would u use and wot would the colour change be with:
    chlorine
    hcl
    so2
    no2
    and any other peopl can think of
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    sum1 must be able to help me here
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    (Original post by lgs98jonee)
    Could anybody pls help me out with litmus paper tests... Such as what sort of paper would u use and wot would the colour change be with:
    chlorine
    hcl
    so2
    no2
    and any other peopl can think of

    Chlorine- bleaches damp blue litmues paper (or red). With blue litmus it will turn red before bleaching.

    HCl - turns damp blue litmus red
    SO2- "" "" "" (although the standard laboratory test would be to use potassium dichromate paper)
    NO2 (same as above)

    you should also know that NH3 will turn damp red litmus blue.
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    how about the various indicators phenilphtalein, methyl orange, uni indicator etc....wot colours r these when alkaline and acidic?
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    (Original post by lgs98jonee)
    how about the various indicators phenilphtalein, methyl orange, uni indicator etc....wot colours r these when alkaline and acidic?
    pls help wid thuis
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    (Original post by lgs98jonee)
    how about the various indicators phenilphtalein, methyl orange, uni indicator etc....wot colours r these when alkaline and acidic?

    acid----> alkaline Methy Orange-Red to Yellow
    Phenolphtalein- Colourless to Pink
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    Isn't it pink to colourless?
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    so which one???
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    could sum1 confirm whether it is pink to colourless or colourless to pink????? and also wot colour change would u have with potassium dischromate paper and SO2??
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    (Original post by lgs98jonee)
    could sum1 confirm whether it is pink to colourless or colourless to pink????? and also wot colour change would u have with potassium dischromate paper and SO2??
    helllllllpppppp.....plsssss!!! :confused: :confused:
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    ne1?
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    Potassium dichromate would go from orange to green as the dichromate is being reduced. It always goes that way, like manganate always goes purple to brown.

    phenolphthalien is pink in alkali and colourless in acid. I'm not sure about the methyl orange one.
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    phenylphalein is colourless in acid, pink in alkali
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    (Original post by mik1a)
    Potassium dichromate would go from orange to green as the dichromate is being reduced. It always goes that way, like manganate always goes purple to brown.

    phenolphthalien is pink in alkali and colourless in acid. I'm not sure about the methyl orange one.
    tx so potassium dichromate paper would act the same as acidified potas...
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    (Original post by lgs98jonee)
    tx so potassium dichromate paper would act the same as acidified potas...
    Yes, in general, but they have different formulas so require different moles of H+ ions etc.... make sure you use KCr2O7 for sulphur dioxide test.
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    with universal indicator solution...is it purpleish when alkali, red when acidic and green when neutral??
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    yes
 
 
 
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