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    I am making up a starch solution for my OCR salters B chemistry project (iodine clock) and am using a starch indicator to show when the thiosulfate ions have been consumed.

    I am unsure on how to store this solution however, I think it is only effective when made up on the day but I don't know why. Any explanation or methods on storing starch indicator would be great thank you.
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    (Original post by joestevens2092)
    I am making up a starch solution for my OCR salters B chemistry project (iodine clock) and am using a starch indicator to show when the thiosulfate ions have been consumed.

    I am unsure on how to store this solution however, I think it is only effective when made up on the day but I don't know why. Any explanation or methods on storing starch indicator would be great thank you.
    Don't try to store it.

    Starch starts to polymerise by cross branching in solution. You can't store it as it 'goes off' in this way. After a while it will not even give a reaction with iodine.
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    (Original post by charco)
    Don't try to store it.

    Starch starts to polymerise by cross branching in solution. You can't store it as it 'goes off' in this way. After a while it will not even give a reaction with iodine.
    Great reply thanks alot
 
 
 
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