Our teacher while teaching thermodynamics talked about free expansion, isothermal free expansion and adiabatic free expansion.
But for isobaric free expansion, he said that's not possible (it's not a thing) because when the pressure is a constant, volume of gas can't be increased.
But doesn't isobaric expansion mean just that, the volume of gas increasing without pressure changes.
So, is isobaric free expansion a thing? Yes/No? Why?
If the volume of gas increases, but pressure stays the same, then something must be steadily supplying heat.
PV = nRT yields T = PV/nR
If P stays the same, and V increases, so must T.
This is obviously not a system in equilibrium.
A simple example would be a flask with a rubber stopper and glass tube, in which one inserts a drop of water half-way down the tube. The pressure in the flask equals current atmospheric pressure, ignoring the minuscule weight of the droplet. Warm the flask in your hand and the drop ascends: temperature increased, volume increased, pressure unchanged (still balances atmospheric).
