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JSGandora
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Can anyone give an explanation (other than algebraically) as to why one mole of a gas under Standard Temperature and Pressure and behaves like an ideal gas will always have the same volume (22.4 L)?
JSGandora said:Can anyone give an explanation (other than algebraically) as to why one mole of a gas under Standard Temperature and Pressure and behaves like an ideal gas will always have the same volume (22.4 L)?
I don't think you really meant what you said there. The density of a gas, or anything else for that matter, is not fixed.klimatos said:Moreover, for an Ideal Gas, you don't even have to stick with NTP. No matter what the temperature and no matter what the pressure, the number of molecules in a fixed volume will be exactly the same for any gas or any mixture of non-reacting gases.
Andrew Mason said:I don't think you really meant what you said there. The density of a gas, or anything else for that matter, is not fixed.
In the case of a gas: n/V = P/RT
AM
Right. That is true only for any ideal gas, which I think is what you were trying to say.klimatos said:Andrew,
I can see how my wording might be interpreted in a way that I did not intend. What I meant was that for any specific temperature (T) and for any specific pressure (P), the number of molecules per cubic meter (n) is the same for any gas or any mixture of non-reacting gases.
n = P/kT
Gavandeshaq said:I understand that the number of molecules in an isolated system will remain the same, no matter what you expand the volume to, raise the temperature to etc.
But how can the equation N=P/kT (I'm going to assume you meant uppercase N for number of molecules there, rather than lowercase n for moles) be derived from PV=NkT; completely disregarding V?
At standard temperature and pressure (STP), the volume of 1 mole of gas is 22.4 liters. This value is known as the molar volume of a gas and is based on the ideal gas law.
The volume of 1 mole of gas at STP is calculated using the ideal gas law: PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is the temperature (273.15 K at STP).
STP stands for standard temperature and pressure, which is defined as 1 atmosphere of pressure and 0 degrees Celsius (273.15 K) of temperature. This standard is used to measure gas volume because it allows for easy comparison and calculation of gas properties.
Yes, the volume of 1 mole of gas at STP varies for different gases. This is due to the different molecular weights and properties of different gases. For example, 1 mole of helium gas at STP has a volume of 22.4 liters, while 1 mole of carbon dioxide gas at STP has a volume of 44.8 liters.
Avogadro's Law states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules. Therefore, at STP, 1 mole of any gas will occupy the same volume of 22.4 liters, regardless of its molecular weight or properties.