Which condition has the lowest vapor pressure?

To determine which condition has the lowest vapor pressure, it's essential to understand the relationship between temperature, relative humidity (RH), and vapor pressure. Vapor pressure is the pressure exerted by a vapor in equilibrium with its liquid or solid form and is influenced by the temperature and amount of moisture in the air.

In the case of the scenario provided, 53°F at 80% RH has relatively low vapor pressure for several reasons. First, lower temperatures generally correlate with lower vapor pressures because colder air can hold less moisture than warmer air. At 53°F, the air is not capable of maintaining a high vapor pressure, even at 80% RH.

Additionally, while 80% RH indicates a relatively high moisture content compared to the maximum possible at that temperature, the maximum amount of water vapor that can exist at 53°F is still significantly lower than at higher temperatures. Therefore, despite the fact that the relative humidity is relatively high, the absolute amount of moisture in the air at 53°F remains low, leading to a low vapor pressure.

This understanding of the interaction between temperature and humidity allows us to conclude that the condition at 53°F and 80% RH represents the state with the lowest vapor pressure among the choices given.