Answer: In an open system the vapor pressure is equal to the outside air pressure.
Step-by-step explanation:
An open system is a system that is capable of exchanging both matter and energy with its surroundings.
For example, a hot cup of coffee is an open system as the cup is not covered with a lid. Therefore, heat energy from the coffee goes into the surroundings.
Vapor pressure is defined as the ability of a substance to change into vapor state. pressure
Therefore, we can conclude that in an open system the vapor pressure is equal to the outside air pressure.