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help with this moles/amount of substance calculation! watch

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    I'm Kind of stuck on this question. I can get only the moles of ZnSO4 then I don't know what to do!

    13.2 g of a sample of zinc sulphate, ZnSO4.xH2O, was strongly heated until no further change in mass was recorded. On heating, all the water of crystallisation evaporated as follows: ZnSO4.xH2O -----> ZnSO4 + xH2O.
    Calculate the number of moles of water of crystallisation in the zinc sulphate sample given that 7.4 g of solid remained after strong heating.


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    work out moles of ZnSO4? calculate that into mass on the LHS then work out the excess mass which is water, then use mass/mr to find moles of water.
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    (Original post by bambamty)
    work out moles of ZnSO4? calculate that into mass on the LHS then work out the excess mass which is water, then use mass/mr to find moles of water.
    Thanks
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    (Original post by Insanity514)
    Thanks
    No problem matey, did you get it in the end?
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    (Original post by bambamty)
    No problem matey, did you get it in the end?
    ye I got it
 
 
 

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