Property - Maple Help

ThermophysicalData[Chemicals]

 Property
 access thermodynamic data

 Calling Sequence Property(output, species, inputopts, opts)

Parameters

 output - symbol or string for the desired output quantity species - symbol or string representing the required chemical inputopts - (optional) equation of the form s=value, where s is temperature, "temperature", T or "T" opts - (optional) one of more options, as described below

Options

 • useunits : true or false show the output with units
 • explicit : true or false show the output in polynomial form

Description

 • The Property function returns the thermodynamic data defined in McBride et al. (2002) and data on the molar Gibbs free energy of formation that is derived from it.
 • The data returned is at the standard state.
 – If species is a gas, the standard state is 1 bar.
 – If species is crystalline or liquid, the standard state is 1 atm.
 • The output parameter is one of Hmolar, Smolar, Cpmolar, MolarMass,  HeatOfFormation or Comments. It can be given as a symbol or a string. Refer to the tables below for alternative names that are accepted by this command.
 • If output is Hmolar, Gmolar, Smolar or Cpmolar, then an equation of the form temperature=value needs to be supplied.
 – temperature can be replaced by "temperature", T or "T".
 – value can be a name, a numeric value, or a numeric value with a unit of K .
 – If value is a name and explicit is false (the default), then the unevaluated function is returned.
 – If value is a name and explicit=true or explicit is specified, then an expression in value is returned. The expression is an empirical correlation for output as defined in McBride et al. (2002), or data on the molar Gibbs free energy of formation that is derived from such correlations.
 – If value is numeric, then it is assumed to be the temperature in Kelvin.
 – If value is numeric with a unit of K or if useunit=true or useunit is specified, then the result returned by Property will have a unit. No other temperature unit apart from K can be used.
 – This table describes the results returned by the Property command.

 Output Quantity Unit of Returned Value Hmolar, HMOLAR, molar_specific_enthalpy, molarspecificenthalpy Molar enthalpy J/mol Gmolar, GMOLAR, molar_gibbs_free_energy_of_formation, molargibbsfreeenergyofformation Molar Gibbs free energy of formation J/mol Smolar, SMOLAR, molar_specific_entropy, molarspecificentropy Molar entropy J/mol/K Cpmolar, CPMOLAR, molar_specific_constant_pressure_specific_heat, molarspecificconstantpressurespecificheat Molar heat capacity at constant pressure J/mol/K

 • If output is MolarMass or HeatOfFormation, then the following is true.
 – If the option useunit has the value true, the result returned by the Property command will have a unit.
 – This table describes the data returned by the Property command.

 Output Quantity Unit of Returned Value MolarMass, M, MOLARMASS, MOLAR_MASS, MOLEMASS, molar_mass, molemass Molar mass g/mol HeatOfFormation Heat of formation at 298.15 J/mol

 • If output is Comments then additional information (as defined in McBride et al., 2002) about the chemical is returned.

Examples

 > $\mathrm{with}\left(\mathrm{ThermophysicalData}:-\mathrm{Chemicals}\right)$
 $\left[{\mathrm{GetSpecies}}{,}{\mathrm{Property}}\right]$ (1)

Determine the enthalpy of CO2 with and without units

 > $\mathrm{Property}\left(\mathrm{Hmolar},\mathrm{CO2},\mathrm{temperature}=300\right)$
 ${-393441.2212}$ (2)
 > $\mathrm{Property}\left(\mathrm{Hmolar},\mathrm{CO2},\mathrm{temperature}=300⟦K⟧\right)$
 ${-}{393441.2212}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$ (3)

Determine the molecular weight of CO2 with and without units

 > $\mathrm{Property}\left(\mathrm{MolarMass},\mathrm{CO2}\right)$
 ${44.0095000}$ (4)
 > $\mathrm{Property}\left(\mathrm{MolarMass},\mathrm{CO2},\mathrm{useunits}\right)$
 ${44.0095000}{}⟦\frac{{g}}{{\mathrm{mol}}}⟧$ (5)

Return an empirical correlation for the molar enthalpy of CO2

 > $\mathrm{Property}\left("Hmolar","CO2","temperature"=T,\mathrm{explicit}\right)$
 ${8.314510}{}{T}{}\left(\left\{\begin{array}{cc}{-}\frac{{49436.50540}}{{{T}}^{{2}}}{-}\frac{{626.4116010}{}{\mathrm{ln}}{}\left({T}\right)}{{T}}{+}{5.301725240}{+}{0.001251906908}{}{T}{-}{7.091029093}{×}{{10}}^{{-8}}{}{{T}}^{{2}}{-}{1.922497195}{×}{{10}}^{{-10}}{}{{T}}^{{3}}{+}{5.699355602}{×}{{10}}^{{-14}}{}{{T}}^{{4}}{-}\frac{{45281.98460}}{{T}}& {200.000}{\le }{T}{\le }{1000.000}\\ {-}\frac{{117696.2419}}{{{T}}^{{2}}}{-}\frac{{1788.791477}{}{\mathrm{ln}}{}\left({T}\right)}{{T}}{+}{8.291523190}{-}{0.00004611578390}{}{T}{+}{1.621225627}{×}{{10}}^{{-9}}{}{{T}}^{{2}}{-}{4.727633280}{×}{{10}}^{{-13}}{}{{T}}^{{3}}{+}{1.266007318}{×}{{10}}^{{-16}}{}{{T}}^{{4}}{-}\frac{{39083.50590}}{{T}}& {1000.000}{<}{T}{\le }{6000.000}\\ \frac{{1.544423287}{×}{{10}}^{{9}}}{{{T}}^{{2}}}{+}\frac{{1.016847056}{×}{{10}}^{{6}}{}{\mathrm{ln}}{}\left({T}\right)}{{T}}{-}{256.1405230}{+}{0.01684700540}{}{T}{-}{7.270614457}{×}{{10}}^{{-7}}{}{{T}}^{{2}}{+}{1.747855210}{×}{{10}}^{{-11}}{}{{T}}^{{3}}{-}{1.768470300}{×}{{10}}^{{-16}}{}{{T}}^{{4}}{-}\frac{{8.043214510}{×}{{10}}^{{6}}}{{T}}& {6000.000}{<}{T}{\le }{20000.000}\\ {\mathrm{undefined}}& {\mathrm{otherwise}}\end{array}\right\\right)$ (6)

Given an enthalpy, backsolve for the temperature

 > $\mathrm{fsolve}\left(\mathrm{Property}\left("Hmolar","CO2","temperature"=T\right)=-3.938111213{10}^{5}⟦\frac{J}{\mathrm{mol}}⟧,T=280⟦K⟧\right)$
 ${289.9999991}{}⟦{K}⟧$ (7)

Calculate the Gibbs Energy of Formation of ammonia at 298.15 K, given the reaction ${N}_{2}\left(g\right)+3{H}_{2}\left(g\right)\to 2{\mathrm{NH}}_{3}\left(g\right)$

 > $\mathrm{with}\left({\mathrm{Units}}_{\mathrm{Simple}}\right):$

Temperature

 > $T≔298.15⟦'K'⟧$
 ${T}{≔}{298.15}{}⟦{K}⟧$ (8)

Enthalpy

 > $\mathrm{h_N2}≔\mathrm{Property}\left("Hmolar","N2","temperature"=T\right);$$\mathrm{h_H2}≔\mathrm{Property}\left("Hmolar","H2","temperature"=T\right);$$\mathrm{h_NH3}≔\mathrm{Property}\left("Hmolar","NH3","temperature"=T\right)$
 ${\mathrm{h_N2}}{≔}{9.915884626}{×}{{10}}^{{-6}}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$
 ${\mathrm{h_H2}}{≔}{-}{4.957942313}{×}{{10}}^{{-6}}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$
 ${\mathrm{h_NH3}}{≔}{-}{45940.00004}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$ (9)

Entropy

 > $\mathrm{s_N2}≔\mathrm{Property}\left("Smolar","N2","temperature"=T\right);$$\mathrm{s_H2}≔\mathrm{Property}\left("Smolar","H2","temperature"=T\right);$$\mathrm{s_NH3}≔\mathrm{Property}\left("Smolar","NH3","temperature"=T\right)$
 ${\mathrm{s_N2}}{≔}{191.6097115}{}⟦\frac{{J}}{{\mathrm{mol}}{}{K}}⟧$
 ${\mathrm{s_H2}}{≔}{130.6810143}{}⟦\frac{{J}}{{\mathrm{mol}}{}{K}}⟧$
 ${\mathrm{s_NH3}}{≔}{192.7702891}{}⟦\frac{{J}}{{\mathrm{mol}}{}{K}}⟧$ (10)

Change in enthalpy and entropy per mole of NH3

 > $\mathrm{DeltaH}≔0.5\left(2\mathrm{h_NH3}-\mathrm{h_N2}-3\mathrm{h_H2}\right);$$\mathrm{DeltaS}≔0.5\left(2\mathrm{s_NH3}-\mathrm{s_N2}-3\mathrm{s_H2}\right)$
 ${\mathrm{DeltaH}}{≔}{-}{45940.00004}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$
 ${\mathrm{DeltaS}}{≔}{-}{99.05608810}{}⟦\frac{{J}}{{\mathrm{mol}}{}{K}}⟧$ (11)

Hence the Gibbs Energy of Formation

 > $\mathrm{DeltaG}≔\mathrm{DeltaH}-\mathrm{DeltaS}T$
 ${\mathrm{DeltaG}}{≔}{-}{16406.42737}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$ (12)
 > $\mathrm{convert}\left(\mathrm{DeltaG},'\mathrm{units}',\frac{'\mathrm{kJ}'}{'\mathrm{mol}'}\right)$
 ${-}{16.40642737}{}⟦\frac{{\mathrm{kJ}}}{{\mathrm{mol}}}⟧$ (13)

Verification:

 > $\mathrm{Property}\left("Gmolar","NH3","temperature"=T,'\mathrm{useunits}'\right)$
 ${-}{16406.42733}{}⟦\frac{{J}}{{\mathrm{mol}}}⟧$ (14)

References

 McBride, Bonnie J.; Zehe, Michael J.; and Gordon, Sanford. NASA Glenn Coefficients for Calculating Thermodynamic Properties of Individual Species; 2002; https://www.grc.nasa.gov/WWW/CEAWeb/TP-2002-21556.htm (6 Dec 2017).

Compatibility

 • The ThermophysicalData:-Chemicals:-Property command was introduced in Maple 2018.