Final answer:
Percent relative humidity is the ratio of vapor density to saturation vapor density and can be calculated by dividing these values.
At 100% relative humidity, the air is at its maximum water vapor capacity for that temperature, known as the dew point. Vapor pressure of water influences the equilibrium between water in its liquid and vapor phases.
Step-by-step explanation:
The ratio of the air's water vapor content to its potential water capacity at a given temperature is known as percent relative humidity. This is determined by dividing the vapor density by the saturation vapor density.
For example, if the air contains 9.40 g/m³ of water vapor, and the saturation vapor density at a certain temperature (such as 10.0°C) is 23.0 g/m³, then the relative humidity can be calculated as 9.40 g/m³ divided by 23.0 g/m³, resulting in approximately 40.87% relative humidity.
It's important to note that the relative humidity will be 100% when the vapor density equals the saturation vapor density; at this point, the air has reached its maximum water vapor capacity at that temperature, which is described as the dew point.
Furthermore, the vapor pressure of water at a given temperature helps us understand the point of equilibrium where water vapor pressure in the air equals the pressure exerted by evaporating water.