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How did i get this number!? - URGENT HELP! watch

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    I have a quantitative practical exam tomorrow for chemistry and i have completely confused myself on my notes.

    In my notes i have go the following calculations:

    first second

    Mass of crucible (g) : 38.00 39.74

    Mass of crucible +
    hydrated salt (g) 39.47 40.82

    Mass of crucible +
    anhydrous salt (g) 39.17 40.46

    ________________________________ ____________________

    Mass of hydrated salt
    used (38.00 - 39.47) (39.74 - 40.82)
    = 1.47 = 1.08

    Mass of salt formed (38.00 - 39.17) (39.74 - 40.46)
    = 1.17 = 0.72

    Mass of water removed
    (1.17 - 1.47) (0.72 - 1.08)
    = 0.30 = 0.36

    ________________________________ ______________________
    Mean

    1.47 1.08 1.28

    1.17 0.72 0.98

    0.30 0.36 0.33

    ________________________________ _________________________

    Moles of water removed: 0.33/18 = 0.0183 mol

    XSO4 . 5H2O --> formulae of (-) ion = SO4 2- Formulae of (+) ion = X2+
    ________________________________ __________________________

    Moles of XSO4 Formed: Ration - XSO4 - 1 : 5 - 5H2O

    N= M/Mr = 0.0183/ 5 = 0.00366 moles

    THE BIT I DONT UNDERSTAND

    MOLAR MASS OF X: Mr = M/N 0.95 / 0.00366

    Where does the mass 0.95 come from???

    Please help me urgently! as i cannot continue the calculation until i understand how i got this?
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    (sorry for the messed up layout - the numbers next to each other are the first test and the second test )
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    I assume it will be mass of anhydrous salt, take away the mass of water driven off from the mass of the hydrated salt?
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    (Original post by matthew769)
    I assume it will be mass of anhydrous salt, take away the mass of water driven off from the mass of the hydrated salt?
    ahh thank you so much!!
 
 
 
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