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Calculating total moles when ions dissolve in water? watch

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    So I need to calculate the total moles of ions released when each of the following dissolves in water.

    a)0.61 mol Rb2SO4
    b) 3.85x10^-3g CaCl2
    c)0.2 mol sucrose
    d)3.7x10^25 molecular units of ammonium bichromate

    I just need clarification on c)

    Since sucrose is C12H22O11, would the ions released be C12, H22 and O11?
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    sucrose has 8 OH groups which I suppose dissociate in water to form H+ ions.
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    (Original post by tremen222)
    sucrose has 8 OH groups which I suppose dissociate in water to form H+ ions.
    No, hydroxyl groups do not dissociate in water.
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    (Original post by charco)
    No, hydroxyl groups do not dissociate in water.
    I was thinking that, although it does depend on whether the pKa of sucrose is >14.
    Does the question mean then that the sucrose hydrolyses into glucose and fructose?
    Alternatively it could be that the answer is just 0 moles as sucrose does not ionise at all in water.
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    (Original post by tremen222)
    I was thinking that, although it does depend on whether the pKa of sucrose is >14.
    Does the question mean then that the sucrose hydrolyses into glucose and fructose?
    Alternatively it could be that the answer is just 0 moles as sucrose does not ionise at all in water.
    You are overthinking the question.

    Sucrose is simple covalent and does not produce ions when dissolved.
 
 
 
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