diff --git a/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.C b/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.C
index fcf5da9ae..691815e2c 100644
--- a/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.C
+++ b/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.C
@@ -137,9 +137,9 @@ void Foam::phaseProperties::setCarrierIds
 void Foam::phaseProperties::checkTotalMassFraction() const
 {
     scalar total = 0.0;
-    forAll(Y_, cmptI)
+    forAll(Y_, speciei)
     {
-        total += Y_[cmptI];
+        total += Y_[speciei];
     }
 
     if (Y_.size() != 0 && mag(total - 1.0) > SMALL)
@@ -147,9 +147,9 @@ void Foam::phaseProperties::checkTotalMassFraction() const
         FatalErrorIn
         (
             "void phaseProperties::checkTotalMassFraction() const"
-        )   << "Component fractions must total to unity for phase "
+        )   << "Specie fractions must total to unity for phase "
             << phaseTypeNames[phase_] << nl
-            << "Components: " << nl << names_ << nl
+            << "Species: " << nl << names_ << nl
             << exit(FatalError);
     }
 }
@@ -227,38 +227,33 @@ void Foam::phaseProperties::reorder
     const wordList& solidNames
 )
 {
-    // Determine the addressing to map between components listed in the phase
+    // Determine the addressing to map between species listed in the phase
     // with those given in the (main) thermo properties
     switch (phase_)
     {
         case GAS:
         {
-            reorder(gasNames);
-            forAll(carrierIds_, i)
-            {
-                carrierIds_[i] = i;
-            }
+            // The list of gaseous species in the mixture may be a sub-set of
+            // the gaseous species in the carrier phase
+            setCarrierIds(gasNames);
             break;
         }
         case LIQUID:
         {
+            // Set the list of liquid species to correspond to the complete list
+            // defined in the thermodynamics package.
             reorder(liquidNames);
+            // Set the ids of the corresponding species in the carrier phase
             setCarrierIds(gasNames);
             break;
         }
         case SOLID:
         {
+            // Set the list of solid species to correspond to the complete list
+            // defined in the thermodynamics package.
             reorder(solidNames);
-            WarningIn
-            (
-                "phaseProperties::reorder"
-                "("
-                    "const wordList& gasNames, "
-                    "const wordList& liquidNames, "
-                    "const wordList& solidNames"
-                ")"
-            )   << "Assuming no mapping between solid and carrier species"
-                << endl;
+            // Assume there is no correspondence between the solid species and
+            // the species in the carrier phase (no sublimation).
             break;
         }
         default:
@@ -303,19 +298,19 @@ const Foam::List<Foam::word>& Foam::phaseProperties::names() const
 }
 
 
-const Foam::word& Foam::phaseProperties::name(const label cmptI) const
+const Foam::word& Foam::phaseProperties::name(const label speciei) const
 {
-    if (cmptI >= names_.size())
+    if (speciei >= names_.size())
     {
         FatalErrorIn
         (
             "const word& phaseProperties::name(const label) const"
-        )   << "Requested component " << cmptI << "out of range" << nl
-            << "Available phase components:" << nl << names_ << nl
+        )   << "Requested specie " << speciei << "out of range" << nl
+            << "Available phase species:" << nl << names_ << nl
             << exit(FatalError);
     }
 
-    return names_[cmptI];
+    return names_[speciei];
 }
 
 
@@ -325,19 +320,19 @@ const Foam::scalarField& Foam::phaseProperties::Y() const
 }
 
 
-Foam::scalar& Foam::phaseProperties::Y(const label cmptI)
+Foam::scalar& Foam::phaseProperties::Y(const label speciei)
 {
-    if (cmptI >= Y_.size())
+    if (speciei >= Y_.size())
     {
         FatalErrorIn
         (
             "const scalar& phaseProperties::Y(const label) const"
-        )   << "Requested component " << cmptI << "out of range" << nl
-            << "Available phase components:" << nl << names_ << nl
+        )   << "Requested specie " << speciei << "out of range" << nl
+            << "Available phase species:" << nl << names_ << nl
             << exit(FatalError);
     }
 
-    return Y_[cmptI];
+    return Y_[speciei];
 }
 
 
@@ -347,13 +342,13 @@ const Foam::labelList& Foam::phaseProperties::carrierIds() const
 }
 
 
-Foam::label Foam::phaseProperties::id(const word& cmptName) const
+Foam::label Foam::phaseProperties::id(const word& specieName) const
 {
-    forAll(names_, cmptI)
+    forAll(names_, speciei)
     {
-        if (names_[cmptI] == cmptName)
+        if (names_[speciei] == specieName)
         {
-            return cmptI;
+            return speciei;
         }
     }
 
diff --git a/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.H b/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.H
index 3d68491e0..334f0e6d4 100644
--- a/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.H
+++ b/src/lagrangian/intermediate/phaseProperties/phaseProperties/phaseProperties.H
@@ -25,7 +25,7 @@ Class
     Foam::phaseProperties
 
 Description
-    Helper class to manage multi-component phase properties
+    Helper class to manage multi-specie phase properties
 
 SourceFiles
     phaseProperties.C
@@ -79,10 +79,10 @@ private:
         //- State label (s), (l), (g) etc.
         word stateLabel_;
 
-        //- List of component names
+        //- List of specie names
         List<word> names_;
 
-        //- List of component mass fractions
+        //- List of specie mass fractions
         scalarField Y_;
 
         //- Map to carrier id
@@ -145,24 +145,24 @@ public:
             //- Return word representation of the phase type
             word phaseTypeName() const;
 
-            //- Return the list of component names
+            //- Return the list of specie names
             const List<word>& names() const;
 
-            //- Return const access to a component name
-            const word& name(const label cmptI) const;
+            //- Return const access to a specie name
+            const word& name(const label speciei) const;
 
-            //- Return const access to all component mass fractions
+            //- Return const access to all specie mass fractions
             const scalarField& Y() const;
 
-            //- Return non-const access to a component mass fraction
-            scalar& Y(const label cmptI);
+            //- Return non-const access to a specie mass fraction
+            scalar& Y(const label speciei);
 
             //- Return const access to the map to the carrier ids
             const labelList& carrierIds() const;
 
-            //- Return the id of a component in the local list by name
+            //- Return the id of a specie in the local list by name
             //  Returns -1 if not found
-            label id(const word& cmptName) const;
+            label id(const word& specieName) const;
 
 
     // IOstream Operators
diff --git a/src/lagrangian/intermediate/submodels/Reacting/CompositionModel/CompositionModel/CompositionModel.C b/src/lagrangian/intermediate/submodels/Reacting/CompositionModel/CompositionModel/CompositionModel.C
index 7cb6e81bf..2b4e987a7 100644
--- a/src/lagrangian/intermediate/submodels/Reacting/CompositionModel/CompositionModel/CompositionModel.C
+++ b/src/lagrangian/intermediate/submodels/Reacting/CompositionModel/CompositionModel/CompositionModel.C
@@ -147,9 +147,9 @@ const Foam::wordList& Foam::CompositionModel<CloudType>::stateLabels() const
 
 template<class CloudType>
 const Foam::wordList&
-Foam::CompositionModel<CloudType>::componentNames(const label phaseI) const
+Foam::CompositionModel<CloudType>::componentNames(const label phasei) const
 {
-    return phaseProps_[phaseI].names();
+    return phaseProps_[phasei].names();
 }
 
 
@@ -166,7 +166,7 @@ Foam::label Foam::CompositionModel<CloudType>::carrierId
     {
         FatalErrorIn
         (
-            "Foam::label Foam::CompositionModel<CloudType>::carrierId"
+            "label CompositionModel<CloudType>::carrierId"
             "("
                 "const word&, "
                 "const bool"
@@ -184,18 +184,18 @@ Foam::label Foam::CompositionModel<CloudType>::carrierId
 template<class CloudType>
 Foam::label Foam::CompositionModel<CloudType>::localId
 (
-    const label phaseI,
+    const label phasei,
     const word& cmptName,
     const bool allowNotFound
 ) const
 {
-    label id = phaseProps_[phaseI].id(cmptName);
+    label id = phaseProps_[phasei].id(cmptName);
 
     if (id < 0 && !allowNotFound)
     {
         FatalErrorIn
         (
-            "Foam::label Foam::CompositionModel<CloudType>::localId"
+            "label CompositionModel<CloudType>::localId"
             "("
                 "const label, "
                 "const word&, "
@@ -212,26 +212,26 @@ Foam::label Foam::CompositionModel<CloudType>::localId
 template<class CloudType>
 Foam::label Foam::CompositionModel<CloudType>::localToCarrierId
 (
-    const label phaseI,
+    const label phasei,
     const label id,
     const bool allowNotFound
 ) const
 {
-    label cid = phaseProps_[phaseI].carrierIds()[id];
+    label cid = phaseProps_[phasei].carrierIds()[id];
 
     if (cid < 0 && !allowNotFound)
     {
         FatalErrorIn
         (
-            "Foam::label "
-            "Foam::CompositionModel<CloudType>::localToCarrierId"
+            "label "
+            "CompositionModel<CloudType>::localToCarrierId"
             "("
                 "const label, "
                 "const label, "
                 "const bool"
             ") const"
         )   << "Unable to determine global carrier id for phase "
-            << phaseI << " with local id " << id
+            << phasei << " with local id " << id
             << abort(FatalError);
     }
 
@@ -242,22 +242,22 @@ Foam::label Foam::CompositionModel<CloudType>::localToCarrierId
 template<class CloudType>
 const Foam::scalarField& Foam::CompositionModel<CloudType>::Y0
 (
-    const label phaseI
+    const label phasei
 ) const
 {
-    return phaseProps_[phaseI].Y();
+    return phaseProps_[phasei].Y();
 }
 
 
 template<class CloudType>
 Foam::scalarField Foam::CompositionModel<CloudType>::X
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
-    scalarField X(Y.size(), 0.0);
+    const phaseProperties& props = phaseProps_[phasei];
+    scalarField X(Y.size());
     scalar WInv = 0.0;
     switch (props.phase())
     {
@@ -265,8 +265,9 @@ Foam::scalarField Foam::CompositionModel<CloudType>::X
         {
             forAll(Y, i)
             {
-                WInv += Y[i]/thermo_.carrier().W(i);
-                X[i] = Y[i]/thermo_.carrier().W(i);
+                label cid = props.carrierIds()[i];
+                X[i] = Y[i]/thermo_.carrier().W(cid);
+                WInv += X[i];
             }
             break;
         }
@@ -274,8 +275,8 @@ Foam::scalarField Foam::CompositionModel<CloudType>::X
         {
             forAll(Y, i)
             {
-                WInv += Y[i]/thermo_.liquids().properties()[i].W();
-                X[i] += Y[i]/thermo_.liquids().properties()[i].W();
+                X[i] = Y[i]/thermo_.liquids().properties()[i].W();
+                WInv += X[i];
             }
             break;
         }
@@ -283,7 +284,7 @@ Foam::scalarField Foam::CompositionModel<CloudType>::X
         {
             FatalErrorIn
             (
-                "Foam::scalarField Foam::CompositionModel<CloudType>::X"
+                "scalarField CompositionModel<CloudType>::X"
                 "("
                     "const label, "
                     "const scalarField&"
@@ -293,21 +294,22 @@ Foam::scalarField Foam::CompositionModel<CloudType>::X
         }
     }
 
-    tmp<scalarField> tfld = X/WInv;
-    return tfld();
+    X /= WInv;
+
+    return X;
 }
 
 
 template<class CloudType>
 Foam::scalar Foam::CompositionModel<CloudType>::H
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y,
     const scalar p,
     const scalar T
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
+    const phaseProperties& props = phaseProps_[phasei];
     scalar HMixture = 0.0;
     switch (props.phase())
     {
@@ -315,7 +317,8 @@ Foam::scalar Foam::CompositionModel<CloudType>::H
         {
             forAll(Y, i)
             {
-                HMixture += Y[i]*thermo_.carrier().Ha(i, p, T);
+                label cid = props.carrierIds()[i];
+                HMixture += Y[i]*thermo_.carrier().Ha(cid, p, T);
             }
             break;
         }
@@ -344,7 +347,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::H
         {
             FatalErrorIn
             (
-                "Foam::scalar Foam::CompositionModel<CloudType>::H"
+                "scalar CompositionModel<CloudType>::H"
                 "("
                 "    const label, "
                 "    const scalarField&, "
@@ -362,13 +365,13 @@ Foam::scalar Foam::CompositionModel<CloudType>::H
 template<class CloudType>
 Foam::scalar Foam::CompositionModel<CloudType>::Hs
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y,
     const scalar p,
     const scalar T
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
+    const phaseProperties& props = phaseProps_[phasei];
     scalar HsMixture = 0.0;
     switch (props.phase())
     {
@@ -376,7 +379,8 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hs
         {
             forAll(Y, i)
             {
-                HsMixture += Y[i]*thermo_.carrier().Hs(i, p, T);
+                label cid = props.carrierIds()[i];
+                HsMixture += Y[i]*thermo_.carrier().Hs(cid, p, T);
             }
             break;
         }
@@ -405,7 +409,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hs
         {
             FatalErrorIn
             (
-                "Foam::scalar Foam::CompositionModel<CloudType>::Hs"
+                "scalar CompositionModel<CloudType>::Hs"
                 "("
                 "    const label, "
                 "    const scalarField&, "
@@ -424,13 +428,13 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hs
 template<class CloudType>
 Foam::scalar Foam::CompositionModel<CloudType>::Hc
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y,
     const scalar p,
     const scalar T
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
+    const phaseProperties& props = phaseProps_[phasei];
     scalar HcMixture = 0.0;
     switch (props.phase())
     {
@@ -438,7 +442,8 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hc
         {
             forAll(Y, i)
             {
-                HcMixture += Y[i]*thermo_.carrier().Hc(i);
+                label cid = props.carrierIds()[i];
+                HcMixture += Y[i]*thermo_.carrier().Hc(cid);
             }
             break;
         }
@@ -463,7 +468,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hc
         {
             FatalErrorIn
             (
-                "Foam::scalar Foam::CompositionModel<CloudType>::Hc"
+                "scalar CompositionModel<CloudType>::Hc"
                 "("
                 "    const label, "
                 "    const scalarField&, "
@@ -482,13 +487,13 @@ Foam::scalar Foam::CompositionModel<CloudType>::Hc
 template<class CloudType>
 Foam::scalar Foam::CompositionModel<CloudType>::Cp
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y,
     const scalar p,
     const scalar T
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
+    const phaseProperties& props = phaseProps_[phasei];
     scalar CpMixture = 0.0;
     switch (props.phase())
     {
@@ -496,7 +501,8 @@ Foam::scalar Foam::CompositionModel<CloudType>::Cp
         {
             forAll(Y, i)
             {
-                CpMixture += Y[i]*thermo_.carrier().Cp(i, p, T);
+                label cid = props.carrierIds()[i];
+                CpMixture += Y[i]*thermo_.carrier().Cp(cid, p, T);
             }
             break;
         }
@@ -520,7 +526,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::Cp
         {
             FatalErrorIn
             (
-                "Foam::scalar Foam::CompositionModel<CloudType>::Cp"
+                "scalar CompositionModel<CloudType>::Cp"
                 "("
                     "const label, "
                     "const scalarField&, "
@@ -539,13 +545,13 @@ Foam::scalar Foam::CompositionModel<CloudType>::Cp
 template<class CloudType>
 Foam::scalar Foam::CompositionModel<CloudType>::L
 (
-    const label phaseI,
+    const label phasei,
     const scalarField& Y,
     const scalar p,
     const scalar T
 ) const
 {
-    const phaseProperties& props = phaseProps_[phaseI];
+    const phaseProperties& props = phaseProps_[phasei];
     scalar LMixture = 0.0;
     switch (props.phase())
     {
@@ -555,7 +561,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::L
             {
                 WarningIn
                 (
-                    "Foam::scalar Foam::CompositionModel<CloudType>::L"
+                    "scalar CompositionModel<CloudType>::L"
                     "("
                         "const label, "
                         "const scalarField&, "
@@ -580,7 +586,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::L
             {
                 WarningIn
                 (
-                    "Foam::scalar Foam::CompositionModel<CloudType>::L"
+                    "scalar CompositionModel<CloudType>::L"
                     "("
                         "const label, "
                         "const scalarField&, "
@@ -595,7 +601,7 @@ Foam::scalar Foam::CompositionModel<CloudType>::L
         {
             FatalErrorIn
             (
-                "Foam::scalar Foam::CompositionModel<CloudType>::L"
+                "scalar CompositionModel<CloudType>::L"
                 "("
                     "const label, "
                     "const scalarField&, "
diff --git a/tutorials/lagrangian/coalChemistryFoam/simplifiedSiwek/constant/coalCloud1Properties b/tutorials/lagrangian/coalChemistryFoam/simplifiedSiwek/constant/coalCloud1Properties
index f0ee4a310..1f79c8850 100644
--- a/tutorials/lagrangian/coalChemistryFoam/simplifiedSiwek/constant/coalCloud1Properties
+++ b/tutorials/lagrangian/coalChemistryFoam/simplifiedSiwek/constant/coalCloud1Properties
@@ -142,11 +142,6 @@ subModels
                 CH4             0.604;
                 H2              0.099;
                 CO2             0.297;
-
-                // Temporarily add entries for remaining gas species
-                N2  0;
-                O2  0;
-                H2O 0;
             }
             liquid
             {