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Hi can someone please help me with couple of my lab questions .

  1. Nov 28, 2006 #1
    1. The problem statement, all variables and given/known data

    k so we are doin a lab on determining the chemical formula of a hydrate (CuSO4.xH20) wat i need help on is these following questions:
    1. suppose the hydrate was heated too quickly and some of it was lost as it spattered out of the container explain how this would affect
    a) the calculated percent by mass of water in the compound.
    b) the molecular formual you determined.

    wat i think da answer to
    1a) wuld bee that mass wuld change cuz some of solution spattered and since it was heated too quickly da water is not completely evaporated :confused:

    and for 1b) da molecular formula wuld change cuz thur wuld be more water molecules....

    nd other question i dont get is that
    2.how wuld u determine the molecular formual of CuSO4.xH20
    based on this information
    Mass of empty beaker or evaporating dish - 185.6g
    Mass of beaker or evaporating dish + hydrated copper (II) sulfate. 190.1g
    Mass of beaker or evaporating dish + anhydrous copper (II) sulfate. 191.2g

    do u hafto find X first :confused: ?
  2. jcsd
  3. Nov 29, 2006 #2
    Wow my chemistry is very bad. I can't really help you specifically. But for 1a) simply stating that it changes is not enough. You have to state whether it increase, or decreases, or if it stays the same and why. Would it really change? Think about what it is that you calculated (percent by mass of water in compound).

    1b) Again must state how it would change. Why would there be an increase in water molecules when you have less water now?
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