PV=nRT and concentration
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PV=nRT and concentration
I am still confused as to why n/V gives us Molarity or concentration. Can someone enlighten me?
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Re: PV=nRT and concentration
Molarity is given by doing (mol/volume). n is the number of moles, while V stands for volume so by doing n/V, it gives molarity, which is equivalent to the concentration(why we include molarity inside [] not only moles! Hope this helps!
Re: PV=nRT and concentration
Hey! Molarity (M) is moles/liter. n/V is moles/volume and volume would be in liters, thus giving us molarity.
Re: PV=nRT and concentration
Molarity and concentration are the same for the purpose of these problems. Just remember that molarity is mol/volume (L), and "n" refers to moles.
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Re: PV=nRT and concentration
n is the number of moles in our experiment, while V stands for volume (often in terms of liters). When we do n/V, we get moles per liter, which is the unit we use for concentration.
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Re: PV=nRT and concentration
n represents the moles while L represents Liters/ volume of the solution, which then gives us mol/L or molarity.
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Re: PV=nRT and concentration
Molarity = mol/L
And n, in this case, represents mol
V would be liters(L)
And n, in this case, represents mol
V would be liters(L)
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Re: PV=nRT and concentration
Hi! Good question, and I agree with the answers above. Since we know that M = mol/L (where M is molar concentration, mol represents moles, and L represents volume in liters), after substituting in "n" for the number of moles and "V" for the volume, we can see that concentration equals n/V. I hope this was helpful! Have a wonderful weekend!
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Re: PV=nRT and concentration
Hi! So, in the PV = nRT equation, here are what all the variables represent which will help.
P = pressure in atm, V = volume in L, n = moles, R = gas constant ( 8.206 x 10-2 L·atm·K-1·mol-1, for example), and T = temperature in K.
Most important thing about figuring this out, is understanding Molarity = mol/L. Therefore, through the variables we know, we want to rearrange the equation so we have mol/V = the other variables. In other words, n/V = P/RT. Since n = moles and V is in liters, this is molarity. So, if it helps, you can just change n/V to M. Hope this helps!!
P = pressure in atm, V = volume in L, n = moles, R = gas constant ( 8.206 x 10-2 L·atm·K-1·mol-1, for example), and T = temperature in K.
Most important thing about figuring this out, is understanding Molarity = mol/L. Therefore, through the variables we know, we want to rearrange the equation so we have mol/V = the other variables. In other words, n/V = P/RT. Since n = moles and V is in liters, this is molarity. So, if it helps, you can just change n/V to M. Hope this helps!!
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Re: PV=nRT and concentration
Molarity is a way to describe the concentration specifically in terms of moles per liter. So, the "n" represents moles and "V" represents the volumes in liters. Because these variables are present in the equation, we can rearrange it in order to solve for the concentration.
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Re: PV=nRT and concentration
we can change the n/v into concentration because the definition of molarity is just moles/liters so they are substitutable
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Re: PV=nRT and concentration
Concentration is given by molarity or moles/Liters. Dividing both sides of the equation by V gives us n/V on the right side. Since n=moles and volume can be calculated in liters, n/V=molarity or concentration.
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Re: PV=nRT and concentration
I found it useful to think of concentration in this case as Molarity. Molarity is calculated by taking the number of moles of a solute and dividing by the volume of the solution, or n/V. in the ideal gas law, solving for n/V is thereby solving for concentration.
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Re: PV=nRT and concentration
Molarity, or molar concentration, is defined by the number of moles of solute per liter of solution, mol/L. In the ideal gas law, PV = nRT, n is the number of moles and V is volume, so n/V can be rewritten as concentration (mol/L). I hope this explanation wasn't too confusing!
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Re: PV=nRT and concentration
Concentration refers to the amount of a substance in a solvent. This is why it is calculated by the number of moles of the substance divided by the volume. You would use this when you want to convert between Kp and Kc. If you’re ever confused it’s good to know the units that are involved in the calculation because they would need to cancel out in the end.
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Re: PV=nRT and concentration
If we go back to 14a, recall the molarity equations, it was the moles divided by the volume. This is essentially the same thing except for being apart of a larger equation.
Re: PV=nRT and concentration
molarity, usually in brackets [] like when we try to calculate K or Q by dividing concentration (molarity) of products / concentration (molarity) of reactants, is a measure of moles per liter of chemicals in these reactions. So for the purpose of K and Q problems, the molarity and moles are usually the same because the volume tends to be 1 L.
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Re: PV=nRT and concentration
As everyone else has said, given that molarity is simply moles/liter, liters being a a unit of volume, n/V provides us the molar concentration.
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Re: PV=nRT and concentration
Can you calculate K using all partial pressures, or do you need to convert to concentration?
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Re: PV=nRT and concentration
Molarity is calculated by dividing the moles of a particular substance by the volume of the reaction vessel. When looking at the ideal gas law, n=moles and V=volume, so n/V will give us moles/volume, aka the molarity of that substance.
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Re: PV=nRT and concentration
The definition of molarity is moles per liter. n represents moles and v is the volume which is expressed in liters. So by dividing n/V you get moles/liter which is molarity.
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Re: PV=nRT and concentration
Molarity is measured in moles/Liter. In the expression n/V, n represents moles, and volume (V) is measured in liters. Dividing moles by liters provides the units of Molarity or concentration!
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Re: PV=nRT and concentration
n/V is just moles/volume. It also confused me at first but paying close attention to the actual units it helpful!
Re: PV=nRT and concentration
If you refer back to 14A, you will remember we consider molarity or concentration with mols divided by volume. n/V is the algebraic representation of mols divided by volume.
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Re: PV=nRT and 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: PV=nRT and concentration
n/V resembles moles/volume, n is the symbol for moles and V is the symbol for volume so together, n/v= molarity which is moles over volume.
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Re: PV=nRT and concentration
because its moles over volume, that is the measurement for molarity, therefore n/V is molarity
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Re: PV=nRT and concentration
Molarity (or concentration) is represented in moles / volume, which is the respective unit of measure for molarity (or concentration).
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