pV=nRT


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Arman M 1A
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pV=nRT

Postby Arman M 1A » Thu Jan 31, 2019 8:12 pm

What is pV=nRT used for?

Chem_Mod
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Re: pV=nRT

Postby Chem_Mod » Thu Jan 31, 2019 8:31 pm

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).

fgalasso1b
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Re: pV=nRT

Postby fgalasso1b » Fri Feb 01, 2019 2:33 pm

The ideal gas law demonstrates the relationships between pressure, volume, moles, and temperature. It is crucial to finding different values.

Anmol_cheema_2F
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Re: pV=nRT

Postby Anmol_cheema_2F » Fri Feb 01, 2019 5:09 pm

This equation shows the relationship between pressure, volume, moles, gas constant, and temperature and can be moved around to find these different values.

Xinyi Zeng 4C
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Re: pV=nRT

Postby Xinyi Zeng 4C » Fri Feb 01, 2019 6:41 pm

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

Carissa Young 1K
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Re: pV=nRT

Postby Carissa Young 1K » Fri Feb 01, 2019 8:11 pm

What does the R in this equation stand for?

Anita Wong 1H
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Re: pV=nRT

Postby Anita Wong 1H » Fri Feb 01, 2019 8:13 pm

is is a given constant! should be in the equations sheet or in the problem

Sean_Rodriguez_1J
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Re: pV=nRT

Postby Sean_Rodriguez_1J » Fri Feb 01, 2019 9:20 pm

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.

Tony Chung 2I
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Re: pV=nRT

Postby Tony Chung 2I » Sat Mar 02, 2019 7:03 pm

You can use pv=nrt to find one of the constants like n,t,p,or v.

Charles Gu 1D
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Re: pV=nRT

Postby Charles Gu 1D » Sat Mar 02, 2019 7:06 pm

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.

Porus_Karwa_2E
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Re: pV=nRT

Postby Porus_Karwa_2E » Sat Mar 02, 2019 10:52 pm

We can use it to solve for variables that might be unknown to us from the problem.

Luis_Yepez_1F
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Re: pV=nRT

Postby Luis_Yepez_1F » Sun Mar 03, 2019 10:01 pm

You can use the equation to find any of the variables, so p,V,n and T. R is a constant.

jocelyntzeng
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Re: pV=nRT

Postby jocelyntzeng » Sat Mar 16, 2019 12:55 pm

it can also be used to replace pV with nRT in some equations


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