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This tool calculates Antoine's coefficients from couple temperature/pressure (min, avg and max). It gives valid Antoine's coefficient for formula log10(P)=A-B/(C+T) (log base 10) or formula ln(P)=A-B/(C+T) (natural log) depending on output scale chosen.
For example, if you know that PEthanol_273K=11.7898 mmHg, PEthanol_283K=23.3053 mmHg and PEthanol_293K=43.6367 mmHg then Antoine's coefficients calculated with this tool to be used with formula ln(P)=A-B/(C+T) mmHg are A=18.91222, B=3804.13278 et C=-41.67519 to be used on temperature range 273K to 293K.