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Old Aug 24th 2019, 05:21 AM   #1
Sonim
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The Story Behind Hess Law

My book introduces Thermochemistry with the concept of heat and how a calorimeter works. After that, it explains the story behind Hess Law and says that one of the reasons it was created is because a calorimeter can't calculate fast chemical reactions, but it doesn't really say the problem with it. Why can't it calculate fast chemical reactions? Won't the water in the calorimeter heat up or cool down after some time?
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Old Aug 26th 2019, 10:25 PM   #2
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Originally Posted by Sonim View Post
My book introduces Thermochemistry with the concept of heat and how a calorimeter works. After that, it explains the story behind Hess Law and says that one of the reasons it was created is because a calorimeter can't calculate fast chemical reactions, but it doesn't really say the problem with it. Why can't it calculate fast chemical reactions? Won't the water in the calorimeter heat up or cool down after some time?
During fast reaction heat released per unit time is more which results in more loss of heat to surroundings.
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Old Aug 28th 2019, 08:39 AM   #3
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Why there is more loss to the surroundings? Won't the heat be used to elevate the water temperature?
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Old Sep 5th 2019, 11:54 PM   #4
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When all heat is released abruptly in less time then some heat is lost to surroundings before it is gained by water.
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