diff --git a/src/thermophysicalModels/specie/thermo/thermo/thermoI.H b/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
index 27bb855c43899abb57a3dd7b0b989cee8f8922e2..ab19475edab06bd6389a81c3a6a7620ccbd71feb 100644
--- a/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
+++ b/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
@@ -298,22 +298,15 @@ template<class Thermo, template<class> class Type>
 inline Foam::scalar
 Foam::species::thermo<Thermo, Type>::K(const scalar p, const scalar T) const
 {
-    if (equal(this->nMoles(), SMALL))
+    scalar arg = -this->nMoles()*this->g(p, T)/(this->RR*T);
+
+    if (arg < 600.0)
     {
-        return 1.0;
+        return exp(arg);
     }
     else
     {
-        scalar arg = -this->nMoles()*this->g(p, T)/(this->RR*T);
-
-        if (arg < 600.0)
-        {
-            return exp(arg);
-        }
-        else
-        {
-            return VGREAT;
-        }
+        return VGREAT;
     }
 }