Constant Volume
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Constant Volume
Under constant volume I believe the equation for entropy was something like delta S = n Cv ln(T2/T1). Is this Cv value only different from the Cp value when there is a change in the number of moles of gas in the reaction?
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Re: Constant Volume
Cp and Cv just refer to what is held constant. The two have different values and for ideal gases can be found on the equation sheet.
Re: Constant Volume
The difference between Cv and Cp is that Cv is when volume is constant and Cp is when pressure is constant.
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Re: Constant Volume
Cv refers to the constant when volume is constant, for an ideal gas it is 3/2*8.314. Cp refers to when the pressure is constant and this value is higher at 5/2*8.314. Hope this helps!
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Re: Constant Volume
Cv and Cp are used when there are constant volume and constant pressure, respectively, when the temperature is changing. I believe you use the table which states CV an CP for either atoms, linear, or non-linear molecules.
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Re: Constant Volume
Yes, you can see the difference in Cv and Cp on the equation sheet. The only difference between the two is that Cv is used in systems with constant volume and Cp is used in systems with constant pressure.
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Re: Constant Volume
You would utilize the Cv constant in systems under conditions of constant volume while Cp in systems under conditions of constant pressure.
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Re: Constant Volume
Hi! The Cv constant is used for processes that are done under constant volume and is shown on the reference table to be 3/2*R for ideal gases. Cp is used for constant pressure and is solved as 5/2*R for ideal gases.
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Re: Constant Volume
The Cv value is always less than the Cp value, the constant for Cp is always one more than the constant for Cv. There are different values for linear, non-linear, and monatomic molecules.
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Re: Constant Volume
Cp is used for constant pressure and Cv is used for constant volume. They're just two constants that you can find on the equation sheet were given.
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Re: Constant Volume
The values will be different between the two nevertheless. They represent what is being kept constant. They are sort of independent of each other in a sense. Like ice's C doesn't really have a lot to do with liquid water C. There is a relationship there as it is a similar molecule. But in they are going to be different and cannot be changed to equal each other I believe
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Re: Constant Volume
The different Cs refer to the different heat capacities of ideal gases under what is held constant. Cp for constant pressure, and Cv for constant volume
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Re: Constant Volume
The main difference is the Cv value is when the volume is constant whereas the Cp value is when the pressure is constant.
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Re: Constant Volume
the difference between Cv and Cp is that Cv is when volume is being held constant and Cp is when pressure is constant. i hope this helps!
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Re: Constant Volume
Cv is used when the volume is constant and Cp is used when the pressure is constant. The value for Cp and Cv for monotonic molecules are 5/2R and 3/2R, respectively.
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