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Getting a little mixed up with Real vs. Ideal gasses. Could someone let me know if im thinking about it correctly?
PV = nRT is the ideal gas law
At STP(1 atm, 273 K), 1 mole of an ideal gas occupies 22.4L of volume. We assume molecular volume is negligible, intermolecular forces are negligible.
[P-(an^2)/(V^2)][V-nb] = nRT for a real gas, which is van der waals equation.
Real gas has a larger volume than an ideal gas because molecular volume is NOT negligible.
Real gas has a lower pressure than an ideal gas because of intermolecular forces(attractive).
Real gasses act more like ideal gasses with higher temperature(to break any intermolecular forces) and at low pressure(to minimize interactions between gas molecules)
However, I was reading up on something about total volume vs free volume and that's where my confusion comes in. When we use the ideal gas law, the V is equal to the total volume which is equal to the free volume. When we use van der waals, does the V refer to the total volume or the free volume?
So, at STP, does a real gas have more volume or less volume than an ideal gas?
PV = nRT is the ideal gas law
At STP(1 atm, 273 K), 1 mole of an ideal gas occupies 22.4L of volume. We assume molecular volume is negligible, intermolecular forces are negligible.
[P-(an^2)/(V^2)][V-nb] = nRT for a real gas, which is van der waals equation.
Real gas has a larger volume than an ideal gas because molecular volume is NOT negligible.
Real gas has a lower pressure than an ideal gas because of intermolecular forces(attractive).
Real gasses act more like ideal gasses with higher temperature(to break any intermolecular forces) and at low pressure(to minimize interactions between gas molecules)
However, I was reading up on something about total volume vs free volume and that's where my confusion comes in. When we use the ideal gas law, the V is equal to the total volume which is equal to the free volume. When we use van der waals, does the V refer to the total volume or the free volume?
So, at STP, does a real gas have more volume or less volume than an ideal gas?