n/V = concentration
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n/V = concentration
There was a part in lecture 2 where the professor talks about the formula P=nRT/V and how n/V is just concentrate can anyone explain this ?

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Re: n/V = concentration
That part of the lecture was talking about how you can convert between partial pressures and concentrations for gases.
is the ideal gas law. If we rearrange it to , we notice that is just concentration (). Therefore, if we ever need to convert partial pressure to concentration, we can use the formula .
Hope this helps!
is the ideal gas law. If we rearrange it to , we notice that is just concentration (). Therefore, if we ever need to convert partial pressure to concentration, we can use the formula .
Hope this helps!

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Re: n/V = concentration
Concentration by definition is moles over liters and n in the ideal gas equation represents moles and volume is liters therefore n/V is equal to concentration

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Re: n/V = concentration
It's just rearranging the equation and realizing that molarity=concentration= mol/L

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Re: n/V = concentration
As mentioned, n/V is a simple way for us to find the concentrations for gases by manipulating the ideal gas law. In PV = nRT, we know the variable n represents moles and the variable V represents volume. Just make sure V is in Liters since the units for concentration are typically mol/L.

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Re: n/V = concentration
Concentration is simply moles/liters, which, if you remember from 14A is the same as moles of solute(n)/volume of solution(v), which is equal to molarity(M).

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Re: n/V = concentration
n/V is rearranging the variables to represent concentration because n=mols of x and V is liters!

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Re: n/V = concentration
Accoding to the ideal gas law, PV=nRT. If we divide both sides with V, we could have the equation for pressure: P=(nRT)/V
Because n (in moles) divided by volume V(in liters) would result in concentration (in moles per liter), we could substitute n/V in the equation with concentration.
Therefore, P = concentration*(RT)
Because n (in moles) divided by volume V(in liters) would result in concentration (in moles per liter), we could substitute n/V in the equation with concentration.
Therefore, P = concentration*(RT)

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Re: n/V = concentration
concentration is mol/liters, and n represents the number of moles and V represents volume, which can be measured in liters

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Re: n/V = concentration
As n is the number of moles and V is volume in liters, it is easy to see that n/V is just molarity, which is a measure of concentration.

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Re: n/V = concentration
Tiao Tan 3C wrote:Accoding to the ideal gas law, PV=nRT. If we divide both sides with V, we could have the equation for pressure: P=(nRT)/V
Because n (in moles) divided by volume V(in liters) would result in concentration (in moles per liter), we could substitute n/V in the equation with concentration.
Therefore, P = concentration*(RT)
This answer was very helpful to me and very well explained, thank you!
since n/v just converts to the units of moles/liters, you can assume it's concentration

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Re: n/V = concentration
Hello! We know molarity = moles of solute (mol) / volume of solution (L). When we rearrange the ideal gas law so that n/V, we realize that this is the same thing as mol/L, which is concentration.

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Re: n/V = concentration
Hi! Since molarity (M) is defined as the concentration over the volume, we can manipulate our ideal gas equation to get (n/v) on one side and get P/rt on the other side. This is super helpful to go between molarity and pressure especially since we use a lot of gases in chemical equilibrium.

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Re: n/V = concentration
n=moles and V=volume, which can be liters. And since concentration is mol/L, n/V can mean the exact same thing.
Re: n/V = concentration
Aydin Karatas 1F wrote:That part of the lecture was talking about how you can convert between partial pressures and concentrations for gases.
is the ideal gas law. If we rearrange it to , we notice that is just concentration (). Therefore, if we ever need to convert partial pressure to concentration, we can use the formula .
Hope this helps!
This helps so much! Thanks for explaining.

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 Joined: Wed Sep 30, 2020 9:59 pm
Re: n/V = concentration
besides the discussion above, you can also think of it similar to the density formula: density = mass / volume. In this case, mass would be similar to n and concentration would be like density, if that helps understand the equation better.
Re: n/V = concentration
Remember that molarity and concentration are basically the same thing. The formula for molarity is M=mol (n)/volume (L). So for the formula PV=nRT, we can divide both sides by volume and get P=MRT.
Re: n/V = concentration
so let's say there is a problem where they provide the mols and they are in a certain number of L in a container you would have to find the concentration with is basically mol/L in order to then proceed with the problem?
Re: n/V = concentration
305405193 wrote:so let's say there is a problem where they provide the mols and they are in a certain number of L in a container you would have to find the concentration with is basically mol/L in order to then proceed with the problem?
That depends on the problem but mol/L is a common measurement of concentration in chemistry. In chemical equilibrium questions where you use ICE tables, you would have to use concentration (mol/L).
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