@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:concvar a iop:Variable ;
    rdfs:label "determination of iron concentration in a soil sample by colorimetric analysis using ortho-phenanthroline" ;
    rdfs:comment "determination of iron(II) derived from a soil sample (via acid digestion and dilution) using a colorimetric reaction with o-phenanthroline and measurement of absorbance at 510 nm" ;
    iop:hasConstraint [
      a iop:Constraint ;
      rdfs:label "conversion: reaction with o-phenanthroline" ;
      iop:constrains ex:OoI
    ], [
      a iop:Constraint ;
      rdfs:label "conversion: acid digestion" ;
      iop:constrains ex:Matrix
    ], [
      a iop:Constraint ;
      rdfs:label "conversion: dilution" ;
      iop:constrains ex:Matrix
    ], [
      a iop:Constraint ;
      rdfs:label "condition: at 510 nm wavelength" ;
      iop:constrains ex:Prop
    ] ;
    iop:hasMatrix ex:Matrix ;
    iop:hasObjectOfInterest ex:OoI ;
    iop:hasProperty ex:Prop .

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

ex:OoI
    a iop:Entity ;
    rdfs:label "iron" .

ex:Prop
    a iop:Property ;
    rdfs:label "molar concentration" .