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    how to do question 2 part c?

    Samba123 EricPiphany
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  1. File Type: doc 2.1 Exercise 1 - measuring enthalpy changes.doc (26.5 KB, 94 views)
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    (Original post by thefatone)
    how to do question 2 part c?

    Samba123 EricPiphany
    Magnesium becomes limiting reagent (also your tags don't work)
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    (Original post by thefatone)
    how to do question 2 part c?

    Samba123 EricPiphany
    How much Cu reacts? And you know the molar enthalpy change of the reaction already.
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    (Original post by samb1234)
    Magnesium becomes limiting reagent (also your tags don't work)
    right so turns out when you edit tags in they don't work, beautiful. i'll try to remember and put them in next time xD
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    (Original post by samb1234)
    Magnesium becomes limiting reagent (also your tags don't work)
    Hasn't added the 4.
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    (Original post by EricPiphany)
    How much Cu reacts? And you know the molar enthalpy change of the reaction already.
    1 mol of Cu reacts?

    so atm i have 9.676.7=m*4.18*delta T
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    (Original post by thefatone)
    1 mol of Cu reacts?

    so atm i have 9.676.7=m*4.18*delta T
    Why 1 mol?
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    (Original post by EricPiphany)
    Hasn't added the 4.
    And added an a
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    (Original post by EricPiphany)
    Why 1 mol?
    actually since i have 50 g of Cu could i whap that in the formula?
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    (Original post by thefatone)
    right so turns out when you edit tags in they don't work, beautiful. i'll try to remember and put them in next time xD
    its the spelling that is the issue lol
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    (Original post by samb1234)
    its the spelling that is the issue lol
    oh
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    (Original post by samb1234)
    And added an a
    Good point
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    (Original post by samb1234)
    its the spelling that is the issue lol
    OK take this one for me, l wanna do some FP2.
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    (Original post by samb1234)
    its the spelling that is the issue lol
    help pls
    i've done

    Mol=Mass/mr
    mass=mol*mr
    =1*159.6 which is mr of CuSO4

    then i did 9676.7/(159.6*4.18) and got 14.5K as change in temp
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    (Original post by thefatone)
    help pls
    i've done

    Mol=Mass/mr
    mass=mol*mr
    =1*159.6 which is mr of CuSO4

    then i did 9676.7/(159.6*4.18) and got 14.5K as change in temp
    What did you get for part b?
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    (Original post by thefatone)
    help pls
    i've done

    Mol=Mass/mr
    mass=mol*mr
    =1*159.6 which is mr of CuSO4

    then i did 9676.7/(159.6*4.18) and got 14.5K as change in temp
    I'm doing something atm i'll help in 30 mins
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    (Original post by EricPiphany)
    What did you get for part b?
    ..
    (Original post by thefatone)
    help pls
    i've done

    Mol=Mass/mr
    mass=mol*mr
    =1*159.6 which is mr of CuSO4

    then i did 9676.7/(159.6*4.18) and got 14.5K as change in temp
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    (Original post by thefatone)
    help pls
    i've done

    Mol=Mass/mr
    mass=mol*mr
    =1*159.6 which is mr of CuSO4

    then i did 9676.7/(159.6*4.18) and got 14.5K as change in temp
    Find the number of moles of Mg, then times that by the enthalpy change to get energy change
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    (Original post by EricPiphany)
    What did you get for part b?
    for part b i got 2.43g which was the right answer
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    (Original post by thefatone)
    for part b i got 2.43g which was the right answer
    So now you are using 0.8g. (0.8/2.43)*46.3 will give you the new temp. increase.
 
 
 
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