What is the relationship between vapor density and saturation vapor density at 100% relative humidity?

At 100% relative humidity, the air is fully saturated with water vapor, meaning it cannot hold any more moisture at that temperature. At this point, the actual vapor density, which is the mass of water vapor present in a given volume of air, reaches its maximum capacity. This maximum capacity is defined as the saturation vapor density, which is the amount of water vapor the air can hold at a specific temperature before condensation occurs.

Therefore, when relative humidity is at 100%, the actual vapor density and the saturation vapor density are equal. This indicates that the air is completely filled with moisture, and any additional moisture will cause condensation to occur, leading to clouds or precipitation. Hence, the assertion that the two densities are equal at this state is accurate and reflects fundamental principles of thermodynamics and atmospheric science.