Final answer:
Absolute Humidity is the measure of the actual amount of water vapor present in the air, whereas Relative Humidity is a comparison of the current humidity to the maximum possible at a given temperature, and the Dew Point is the temperature at which the air is fully saturated with water vapor.
Step-by-step explanation:
The condition that represents the actual amount of water vapor present in a mixture of air and water is known as Absolute Humidity. This is a measurement of the water vapor content in the air, typically expressed in grams of water per cubic meter of air (g/m³). On the other hand, Relative Humidity is a measure of how much water vapor is in the air compared to the maximum amount of water vapor the air can hold at that temperature. It is expressed as a percentage. The Dew Point is the temperature at which air reaches 100% relative humidity, causing condensation to begin if air is cooled without changing its pressure or the amount of moisture within it.
For instance, if the air contains 9.40 g/m³ of water vapor, and this is the saturation density at 10.0°C, then 10.0°C is the dew point for that air. At this point, the relative humidity is 100%, which may result in fog formation due to the condensation of water droplets.