# thermo.triple module¶

thermo.triple.Tt(CASRN, AvailableMethods=False, Method=None)[source]

This function handles the retrieval of a chemical’s triple temperature. Lookup is based on CASRNs. Will automatically select a data source to use if no Method is provided; returns None if the data is not available.

Returns data from [R12301231], or a chemical’s melting point if available.

Parameters: Returns: CASRN : string CASRN [-] Tt : float Triple point temperature, [K] methods : list, only returned if AvailableMethods == True List of methods which can be used to obtain Tt with the given inputs Method : string, optional A string for the method name to use, as defined by constants in Tt_methods AvailableMethods : bool, optional If True, function will determine which methods can be used to obtain the Tt for the desired chemical, and will return methods instead of the Tt

Notes

Median difference between melting points and triple points is 0.02 K. Accordingly, this should be more than good enough for engineering applications.

Temperatures are on the ITS-68 scale.

References

 [R12301231] (1, 2) Staveley, L. A. K., L. Q. Lobo, and J. C. G. Calado. “Triple-Points of Low Melting Substances and Their Use in Cryogenic Work.” Cryogenics 21, no. 3 (March 1981): 131-144. doi:10.1016/0011-2275(81)90264-2.

Examples

Ammonia

>>> Tt('7664-41-7')
195.47999999999999

thermo.triple.Pt(CASRN, AvailableMethods=False, Method=None)[source]

This function handles the retrieval of a chemical’s triple pressure. Lookup is based on CASRNs. Will automatically select a data source to use if no Method is provided; returns None if the data is not available.

Returns data from [R12311232], or attempts to calculate the vapor pressure at the triple temperature, if data is available.

Parameters: Returns: CASRN : string CASRN [-] Pt : float Triple point pressure, [Pa] methods : list, only returned if AvailableMethods == True List of methods which can be used to obtain Pt with the given inputs Method : string, optional A string for the method name to use, as defined by constants in Pt_methods AvailableMethods : bool, optional If True, function will determine which methods can be used to obtain the Pt for the desired chemical, and will return methods instead of the Pt

References

 [R12311232] (1, 2) Staveley, L. A. K., L. Q. Lobo, and J. C. G. Calado. “Triple-Points of Low Melting Substances and Their Use in Cryogenic Work.” Cryogenics 21, no. 3 (March 1981): 131-144. doi:10.1016/0011-2275(81)90264-2.

Examples

Ammonia

>>> Pt('7664-41-7')
6079.5