Why is the vapor pressure calculated using Antoine’s equation different from that found in databases?
Thread Content
For example, calculating the saturated vapor pressure of CO2 at different temperatures. The data shows: 0°C at 3485 Kpa, and 20°C at 5727 Kpa. However, the values calculated using the Antoine equation differ significantly lgP = A – B/(t + C). Where A = 9.64177, B = 1284.07, C = 268.432, and t = 20. The calculated value of P is 154835 mmHg, which equals 20593 Kpa. What is the mistake here?
The equation has a range of applicability; this temperature seems to be outside that range. I don’t have the relevant information on hand, so please check the manual again
The temperature range isn’t specified – doesn’t it apply to all temperatures?
There should be a range; it is recommended to refer to officially published manual documents
It can be calculated using the formula below; the saturated vapor pressure obtained from this formula is expressed in Pa.