If the air pressure outside a container changes while the temperature remains constant, the amount of liquid in the container would not be directly affected. The level of the liquid would stay the same.
The volume or amount of a liquid in a container is primarily determined by its own properties, such as its density and the container's dimensions, rather than the external air pressure. The liquid's volume will generally remain constant unless there are other factors at play, such as evaporation or condensation.
However, it's important to note that a change in air pressure can indirectly impact the liquid in the container in certain situations. For example:
Liquid Evaporation: If the air pressure decreases, the boiling point of the liquid may decrease as well. This could result in increased evaporation of the liquid, potentially leading to a decrease in its volume over time.
Liquid Condensation: Conversely, if the air pressure increases, the condensation point of the liquid may decrease. This could cause moisture from the air to condense and accumulate on the surface of the liquid, potentially increasing its volume.
It's worth mentioning that these effects would occur gradually over time and depend on factors such as the specific liquid involved and its vapor pressure. However, in general, a change in external air pressure alone, without any other influencing factors, would not directly alter the amount of liquid in a container.