qp vs qv
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qp vs qv
Hi, what is the distinction between these two terms. I know that qp=delta H but why couldn't qv= delta H?
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Re: qp vs qv
Hi Arielle! qv means heat under constant volume and qp means heat under constant pressure. Either of these two variables could be used for the ∆H value since it just specifies the conditions the heat of the system is placed under. Hope this helps!
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Re: qp vs qv
qv is used in cases where the volume is constant and you are trying to calculate heat. On the other hand, qp is used in cases where there is constant pressure.
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Re: qp vs qv
Qp is heat change at constant pressure while Qv is heat change at constant volume. In the lecture, Lavelle mentioned that Qp is related to the coffee cup calorimeter (pressure remains constant in this case because gases can flow in and out), and Qv is related to the bomb calorimeter.
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Re: qp vs qv
Qp is the heat transfer at constant pressure while Qv is the heat transfer at constant volume. Delta H can represent either Qp or Qv, it just depends on the conditions given.
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Re: qp vs qv
I believe that they both can equal delta H actually! You are probably looking at an example where the heat change is occurring at a constant pressure (volume can change), this is when we use qp. However, qv is used when the heat change is occurring at a constant volume, but this can also equal delta H.
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Re: qp vs qv
qp is used for cases of constant pressure and qv is used for cases of constant volume. Both have their respective uses in different scenarios and experiments.
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Re: qp vs qv
qp is used when the pressure is constant (open beaker), and qv is used when the volume is constant (closed system).
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Re: qp vs qv
Hello! Both qp and qv are used to calculate delta H; however, they have different definitions. Qp is heat under constant pressure, while qv is heat under constant volume. Hope this helps!
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Re: qp vs qv
Qp represents a system with constant pressure while Qv represents a system with constant volume.
Re: qp vs qv
you should be able to tell which notation to use based on the given quantities in the problem, qp for constant pressure and qv for constant volume.
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Re: qp vs qv
Qp means that the chemical reaction is occurring under constant pressure, and Qv means that the reaction is occurring under constant volume.
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Re: qp vs qv
qp would be heat change at a constant pressure while qv is a heat change at a constant volume
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