Skip to main content

Water Vapor Pressure

 

Vapor Pressure of Water

T, °CT, °FPressure, kPaPressure, torrPressure, atm
0 32 0.6113 4.5851 0.0060
5 41 0.8726 6.5450 0.0086
10 50 1.2281 9.2115 0.0121
15 59 1.7056 12.7931 0.0168
20 68 2.3388 17.5424 0.0231
25 77 3.1690 23.7695 0.0313
30 86 4.2455 31.8439 0.0419
35 95 5.6267 42.2037 0.0555
40 104 7.3814 55.3651 0.0728
45 113 9.5898 71.9294 0.0946
50 122 12.3440 92.5876 0.1218
55 131 15.7520 118.1497 0.1555
60 140 19.9320 149.5023 0.1967
65 149 25.0220 187.6804 0.2469
70 158 31.1760 233.8392 0.3077
75 167 38.5630 289.2463 0.3806
80 176 47.3730 355.3267 0.4675
85 185 57.8150 433.6482 0.5706
90 194 70.1170 525.9208 0.6920
95 203 84.5290 634.0196 0.8342
100 212 101.3200 759.9625 1.0000

Water vapor pressure is the pressure exerted by water vapor molecules when they are in equilibrium with liquid water at a given temperature.  It represents the partial pressure of water vapor in a mixture of gases, such as air, when the air is saturated with moisture at a specific temperature.

The concept of water vapor pressure is important in meteorology, as it plays a significant role in the formation of weather phenomena like clouds, precipitation, and humidity levels.  The higher the temperature, the more water vapor the air can hold, so the water vapor pressure increases with rising temperatures.  The relationship between temperature and water vapor pressure follows the Clausius-Clapeyron equation, which describes how the saturation vapor pressure changes with temperature.  This relationship is fundamental in understanding and predicting weather patterns and is also relevant in various fields, including chemistry, biology, and engineering.

P D Logo 1