4A.13

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Nick Fiorentino 1E
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Joined: Wed Sep 18, 2019 12:16 am

4A.13

Postby Nick Fiorentino 1E » Fri Jan 31, 2020 6:50 pm

In the solution, it shows q(reaction) equal to -q(calorimeter). Why is this? And how do you know when to use this method?

Kassidy Ford 1I
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Re: 4A.13

Postby Kassidy Ford 1I » Fri Jan 31, 2020 8:14 pm

just think about the law of conservation of energy. energy cannot be created or destroyed, only transferred. So the positive q(reactants) must have come from a -q(calorimetry).

VPatankar_2L
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Re: 4A.13

Postby VPatankar_2L » Fri Jan 31, 2020 8:17 pm

Since diluted aqueous solutions have similar heat capacities as water, you can assume that the heat capacity of the calorimeter is the same as that of the solution. This would allow the qreaction to equal -qcalorimeter.

Bella Townsend
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Joined: Wed Feb 20, 2019 12:18 am

Re: 4A.13

Postby Bella Townsend » Fri Jan 31, 2020 8:44 pm

Due to the law of conservation of energy, the q of the system is equal to the -q of the surroundings. So when you use a bomb calorimeter, you combust the substance inside. Therefore, the q of the substance is equal to the -q of the bomb calorimeter.

Orrin Zhong 4G
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Joined: Sat Jul 20, 2019 12:16 am

Re: 4A.13

Postby Orrin Zhong 4G » Fri Jan 31, 2020 9:11 pm

The heat released from a reaction [q(reaction)] must go somewhere, so it is absorbed by the calorimeter. Therefore, if the temperature of the reaction decreases, then the heat from the reaction will go to the calorimeter, increasing the temperature of the calorimeter. Thus, q(reaction) = -q(calorimeter).


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