@prefix ex: <http://example.org/iadopt/challenge/> .
@prefix iop: <https://w3id.org/iadopt/ont/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

ex:combustion a iop:Variable ;
    rdfs:label "energy of reaction per mole upon combustion in oxygen of a pure substance" ;
    rdfs:comment "energy released (or taken in) upon combustion of a chemical subtance to form carbon dioxide and water" ;
    iop:hasConstraint [
      a iop:Constraint ;
      rdfs:label "purity of substance (required)" ;
      iop:constrains ex:OoI
    ], [
      a iop:Constraint ;
      rdfs:label "mass of substance (required)" ;
      iop:constrains ex:OoI
    ], [
      a iop:Constraint ;
      rdfs:label "phase of matter (optional)" ;
      iop:constrains ex:OoI
    ], [
      a iop:Constraint ;
      rdfs:label "gas pressure (required)" ;
      iop:constrains ex:Matrix
    ], [
      a iop:Constraint ;
      rdfs:label "percent oxygen in atmosphere (required)" ;
      iop:constrains ex:Matrix
    ] ;
    iop:hasMatrix ex:Matrix ;
    iop:hasObjectOfInterest ex:OoI ;
    iop:hasProperty ex:Prop .

ex:Matrix
    a iop:Entity, iop:System ;
    rdfs:label "combustion reaction" .

ex:OoI
    a iop:Entity ;
    rdfs:label "chemical substance" .

ex:Prop
    a iop:Property ;
    rdfs:label "energy change per amount-of-substance" .