using Pv=nrt
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using Pv=nrt
When can I use PV=nRT? I thought that since it's called the ideal gas law the conditions had to be ideal (pressure and temperature).
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Re: using Pv=nrt
Hi,
Yes, the ideal gas law is only supposed to be used when it's an ideal gas at play, but normally we just assume that the real gases behave in a way that is sufficiently similar to an ideal gas. So I think in general if you don't have changes in temperature or volume it's safe to use the ideal gas law, given that you know the values of the constants.
Hope this helps
Yes, the ideal gas law is only supposed to be used when it's an ideal gas at play, but normally we just assume that the real gases behave in a way that is sufficiently similar to an ideal gas. So I think in general if you don't have changes in temperature or volume it's safe to use the ideal gas law, given that you know the values of the constants.
Hope this helps
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Re: using Pv=nrt
For PV=nRT the assumptions that we have in order to use it is that the pressure if low and the temperature is very high. We also have to assume that the collisions between gas molecules are elastic. In general, I think it's ok to use PV=nRT for the entirety of this class since we haven't really discussed any other alternative.
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Re: using Pv=nrt
For calculations we just assume that all gases we will see will behave like ideal gases in this class, though I believe to use it it should be that the assumptions are low pressure and high temp.
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Re: using Pv=nrt
We use this equation when we are trying to find pressure or volume because when one is changing the other should be a constant. You should also be given the temperature unless that is what you are trying to find if given the constant pressure and volume. n = the amount of moles or grams (depends what is given) and R is a constant that can be found on your equation sheet and with the information given you can figure out which R to use based on the units you are trying to cancel out.
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Re: using Pv=nrt
Hi, in this class we assume that all gases behave as ideal gases. When the temperature is high and the pressure is low, the gas will behave closer to an ideal gas, making PV=nRT more accurate, but we will use it regardless.
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Re: using Pv=nrt
Hi!
The Ideal Gas Law can be used to solve for pressure, volume, temperature, or number of moles when needed. In calculation, we assume that gases behave ideally to broadly apply this equation.
In thermodynamics, we usually use the Ideal Gas Law to solve for pressure in finding work or to plug into the equation w = -PdeltaV = -nRT ln(V2/V1).
I hope this helps!
The Ideal Gas Law can be used to solve for pressure, volume, temperature, or number of moles when needed. In calculation, we assume that gases behave ideally to broadly apply this equation.
In thermodynamics, we usually use the Ideal Gas Law to solve for pressure in finding work or to plug into the equation w = -PdeltaV = -nRT ln(V2/V1).
I hope this helps!
Re: using Pv=nrt
Unless otherwise stated we can often make the assumption that it is an ideal gas and we can therefore use that equation.
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Re: using Pv=nrt
You are right, in the ideal gas law the conditions has to be ideal and it can be used whenever you don't have changes in temperature or volume and you know the values of the constants and most of the other values in the equation.
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Re: using Pv=nrt
I remember from lecture that we can assume that all gases act like ideal gases in this course. Therefore we can assume that using PV=nRT is a valid equation to use.
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Re: using Pv=nrt
In this class, I think we can assume that all of gases will behave like ideal gases. Usually, PV=nRT would be used when the pressure is low and the temperature is high though.
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Re: using Pv=nrt
The equation PV=nRT applies only to an ideal gas, or as an approximation to a real gas that behaves sufficiently like an ideal gas. When you are given 3 of the 4 properties in the equation aka pressure, volume, number of moles, and temperature (R is a constant), then the ideal gas law can be used.
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Re: using Pv=nrt
Lavelle said that we can assume that all gases act as ideal gases in this course so Pv=nrt can be used
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Re: using Pv=nrt
I agree with everyone because all gases are ideal gases so then it is valid to use Pv=nrt.
Re: using Pv=nrt
PV=nRT is used for ideal gases, and something I learned in discussion is we can manipulate the equation to solve for whichever variable we need. For instance, if we needed to find the pressure, we can divide nRT by V to do so.
Re: using Pv=nrt
Usually n/v is isolated as n/V= M(mol/Liter) and R is constant, in case pressure or temperature is needed
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Re: using Pv=nrt
I feel like you would use this equation most when trying to find the pressure of the system.
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