According to Pascal's law, what happens to the pressure of a propane tank as it empties?

Pascal's law states that pressure applied to an enclosed fluid is transmitted undiminished throughout the fluid in all directions. In the context of a propane tank, as the tank empties, the pressure within the tank generally remains uniform throughout its volume even as the amount of propane decreases.

This uniform pressure occurs because the tank is a closed system, and any changes in volume or the presence of liquid propane do not create pressure variations in different areas of the tank; the pressure remains constant until the liquid evaporates and significantly alters the conditions inside the tank.

Therefore, even as propane is used from the tank, the pressure is uniformly distributed unless the liquid propane is completely evacuated or evaporation reduces the vapor pressure to a point where the tank is no longer in equilibrium. This principle helps in understanding the behavior of gases and liquids in confined spaces, illustrating the importance of pressure management in refrigeration and HVAC systems.