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Topic: Heat of a Reaction  (Read 2833 times)

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Offline LHM

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Heat of a Reaction
« on: September 02, 2010, 11:17:55 PM »
The heat of a reaction is measured in a bomb calorimeter. This heat is equal to which thermodynamic quantity?

A)  :delta: E
B)  :delta: G
C)  :delta: H
D)  :delta: S

Why is the answer A instead of C?

Offline ContinuousProcess

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Re: Heat of a Reaction
« Reply #1 on: September 03, 2010, 12:45:45 AM »
A bomb calorimeter is supposed to be an isolated system.

Offline Borek

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Re: Heat of a Reaction
« Reply #2 on: September 03, 2010, 03:31:27 AM »
Does the volume change?
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Offline LHM

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Re: Heat of a Reaction
« Reply #3 on: September 04, 2010, 04:15:22 PM »
Does the volume change?

No? Doesn't volume stay constant in a bomb calorimeter? So P :delta: V =0
And since H=U+P :delta: V, H=U?

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