Saturated vapor pressure at the same temperature
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At the same temperature, which one vaporizes first: the one with a higher saturated vapor pressure or the one with a lower saturated vapor pressure? Please let me know, thanks; points will be given
The saturated vapor pressure of the same medium at the same temperature is the same, or in other words, it remains constant. You mean different media, right?
This post was last edited by Little Chemical Engineer on 2017-7-24 at 08:15. The higher the saturated vapor pressure, the easier it is for a substance to vaporize. If the vapor pressure above the liquid is lower than the saturated vapor pressure, the liquid will evaporate until the vapor pressure equals the saturated vapor pressure. Therefore, the higher the saturated vapor pressure, the easier it is for the liquid to evaporate in order to reach liquid-gas equilibrium. For example, at 19°C and 26°C, the saturated vapor pressure of ethanol is 5.3 kPa and 8.0 kPa respectively, while that of water is 2.3 kPa and 3.2 kPa respectively; therefore, ethanol evaporates more easily than water at room temperature. Taking 26°C as an example, in air the vapor pressure of water reaches 3.2 kPa (a volume fraction of 3%) at which point further evaporation ceases; whereas for ethanol, evaporation stops only when its vapor pressure reaches 8 kPa (a volume fraction of 8%). As a result, a small amount of ethanol quickly turns entirely into a gaseous state.
This post was last edited by Little Chemical Engineer on 2017-7-24 08:06. Repeat repeat repeat repeat repeat repeat
It should be the one with a high saturated vapor pressure that vaporizes first