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Topic: Enthalpy Question  (Read 2215 times)

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Offline positiveion

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Enthalpy Question
« on: April 30, 2011, 03:02:27 PM »



I don't understand number c). i.

The equation I was taught for Heat energy is
Heat energy =  mass*spec heat capacity * deltatemperature

I have no idea why the mass isn't involved in the equation given in the markscheme for question c).i.

Help, please?

Thank you very much!
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Offline Borek

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Re: Enthalpy Question
« Reply #1 on: April 30, 2011, 04:46:57 PM »
Everything is perfectly OK.

What is C, what is n?
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Offline positiveion

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Re: Enthalpy Question
« Reply #2 on: April 30, 2011, 11:18:44 PM »
C is the specific heat capacity of the system.

n is the no. moles.
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Offline UG

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Re: Enthalpy Question
« Reply #3 on: May 01, 2011, 02:14:46 AM »
Quote from: positiveion on April 30, 2011, 03:02:27 PM
The equation I was taught for Heat energy is
Heat energy =  mass*spec heat capacity * deltatemperature
This is a matter of getting the units correct. The formula that you were taught, specific heat capacity has units of J g-1 K-1 or kJ g-1 K-1 whereas here the units are kJ K-1 (ie, no mass involved).
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