pV=nRT
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Re: pV=nRT
pV = nRT is the ideal gas law. This is incredibly useful in calculating an unknown (for example, if you are given pressure, volume, and temperature, you can use this law to find the number of moles).
In practice problems, this is often the first step before doing other calculations (such as solving for work).
In practice problems, this is often the first step before doing other calculations (such as solving for work).
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Re: pV=nRT
The ideal gas law demonstrates the relationships between pressure, volume, moles, and temperature. It is crucial to finding different values.
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Re: pV=nRT
This equation shows the relationship between pressure, volume, moles, gas constant, and temperature and can be moved around to find these different values.
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Re: pV=nRT
This equation if the Ideal Gas Law and relationships between the different variables could be derived from this equation:
Boyle's Law: at constant T and n, V and p have an inverse relationship (pV = constant), p1V1 = p2V2
Charles' Law: at constant p and n, V and T have a direct relationship (V/T = constant), V1T1 = V2T2
Avogadro's Law: at constant T and p, V and n have a direct relationship (V/n = constant), V1n1=V2n2
It can be used to determine the molar mass of gases and volatile liquids as n=m(mass)/M(molar mass),
pV=nRT=RT(m/M) -> M=mRT/pV --(1)
It can also be used to determine the density of a gas:
m/V=pM/RT (derived from (1)) -> m/V=pM/RT -> density = pM/RT
Boyle's Law: at constant T and n, V and p have an inverse relationship (pV = constant), p1V1 = p2V2
Charles' Law: at constant p and n, V and T have a direct relationship (V/T = constant), V1T1 = V2T2
Avogadro's Law: at constant T and p, V and n have a direct relationship (V/n = constant), V1n1=V2n2
It can be used to determine the molar mass of gases and volatile liquids as n=m(mass)/M(molar mass),
pV=nRT=RT(m/M) -> M=mRT/pV --(1)
It can also be used to determine the density of a gas:
m/V=pM/RT (derived from (1)) -> m/V=pM/RT -> density = pM/RT
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Re: pV=nRT
In addition to the many uses labeled above, you can also use the law to calculate work in a constant-pressure system (-P*deltaV) when you are not given either the change in volume or the pressure because assuming that you have been given the change in the moles of gas in the reaction, you can equate P*(delta V) to (delta n)*R*T, with RT being a constant. Dr. Lavelle did an example problem like this in lecture today.
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Re: pV=nRT
PV=NRT is a very versatile equation. You can use it for questions that want you to find a missing variable in the equation after plugging everything in.
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