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

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

Given an enthalpy, backsolve for the temperature

 > $\mathrm{fsolve}\left(\mathrm{Property}\left("Hmolar","CO2","temperature"=T\right)=-393811.1213\mathrm{Unit}\left(\frac{J}{\mathrm{mol}}\right),T=280\mathrm{Unit}\left(K\right)\right)$
 ${289.9999991}{}⟦{K}⟧$ (7)

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

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

Temperature

 > $T≔298.15\mathrm{Unit}\left('K'\right)$
 ${T}{≔}{298.15}{}⟦{K}⟧$ (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

 > $\mathrm{DeltaG}≔\mathrm{DeltaH}-\mathrm{DeltaS}T$
 ${\mathrm{DeltaG}}{≔}{-}{16406.42737}{}⟦\frac{{{m}}^{{2}}{}{\mathrm{kg}}}{{\mathrm{mol}}{}{{s}}^{{2}}}⟧$ (12)
 > $\mathrm{convert}\left(\mathrm{DeltaG},'\mathrm{units}',\frac{'\mathrm{kJ}'}{'\mathrm{mol}'}\right)$
 ${-}{16.40642737}{}⟦\frac{{\mathrm{kJ}}}{{\mathrm{mol}}}⟧$ (13) 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. Compatibility

 • The ThermophysicalData:-Chemicals:-Property command was introduced in Maple 2018.
 • For more information on Maple 2018 changes, see Updates in Maple 2018.