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    Hi there!
    Ok so me and my friend are both lost with this question we have.

    We've basically got a table with some investigations, and we have to predict whether the reaction will happen and if so the products and colour of the resultant product.
    So for the first question it's quite straightforward but on the second the question is

    VO_2^+ (aq) +I^- (aq) then add thiosulfate (VI)
    We don't really understand what the thiosulfate would do to the reaction

    My chemistry teacher fails completely. Her half arsed attempt at explaining this was completely wrong from what we could gather as she kept writing down the wrong equations! She's made me hate this goddamn subeject
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    (Original post by doomhalo)
    Hi there!
    Ok so me and my friend are both lost with this question we have.

    We've basically got a table with some investigations, and we have to predict whether the reaction will happen and if so the products and colour of the resultant product.
    So for the first question it's quite straightforward but on the second the question is

    VO_2^+ (aq) +I^- (aq) then add thiosulfate (VI)
    We don't really understand what the thiosulfate would do to the reaction

    My chemistry teacher fails completely. Her half arsed attempt at explaining this was completely wrong from what we could gather as she kept writing down the wrong equations! She's made me hate this goddamn subeject
    OK so you need to use the Eº values of the VO2+ and I- half equations to decide if the redox reactionis spontaneous (possible)

    In the reaction the vanadium (V) would get reduced and the iodide (-I) would get oxidised..

    E(rxn) = E(red) - E(ox)

    if the value of E(rxn) is positive and greater than 0.3V the reaction is spontaneous and proceeds to completion.

    The thiosulphate reacts with the iodine and reduces it to colourless iodide ions. I suppose this will allow you to see the colour of the species formed by reducing the vanadium (V) species, as there are three possibilities.
 
 
 
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