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  1. #1
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    Default Heat capacity of a coffee cup calorimeter.

    How do you solve for the heat capacity of a calorimeter?

  2. #2
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    Quote Originally Posted by dsterlingwells View Post
    How do you solve for the heat capacity of a calorimeter?
    Post a question! ....

  3. #3
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    example question**

  4. #4
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    ................Hot Water.........Cold Water
    Volume........100mL ............100mL
    Start Temp.....90 C................20 C
    End Temp......54 C................54 C

    What is the heat capacity of the students coffee cup?
    Last edited by dsterlingwells; 07-11-2011 at 12:40 PM.

  5. #5
    Chad
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    For heat capacity look at the unit...should be in J/degree C or cal/degree C (or temperature change in units of Kelvin...same diff). So the heat capacity of a calorimeter is usally calculated by C = q/(delta T).

    This is a super tricky question fyi. If you calculate it out (q=mc(delta T)) using the specific heat of water to be 1 cal/(g(degree C))

    then the hot water gave off 3600cal [q = (100)(1)(-36)]
    whereas the cold water absorbed 3400cal [q = (100)(1)(34)].

    This leaves 200cal unaccounted for; this must be what the coffee cup itself absorbed (assuming no heat lost to the surroundings). Assuming the coffee cup also started at 20 degrees C and ended up at 54 degrees C:

    C = q/(delta T) = 200cal/(34 degrees C) ~ 5.9 cal/(degree C)

    Hope this helps!

  6. #6
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    Yeah i couldn't find a simplified equation for the capacity of the calorimeter. The Kaplan book gives this long explanation but i couldn't understand it. The answer was in J/degree.. so it was 24.6..which goes with your answer.

    thanks!

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