diff --git a/src/Chemistry/Bonds/Implements/BaseBond.cs b/src/Chemistry/Bonds/Implements/BaseBond.cs
index ac8a135..aa34878 100644
--- a/src/Chemistry/Bonds/Implements/BaseBond.cs
+++ b/src/Chemistry/Bonds/Implements/BaseBond.cs
@@ -171,14 +171,16 @@ public abstract class BaseBond
         bond.StructureChanged();
         if (Atom.Compound.Atoms.Contains(bond.Atom))
             return;
-        bond.Atom.HomogeneousMixture.Compounds.Remove(bond.Atom.Compound);
-        bond.Atom.Compound.Amount = 0d;
         
+        Compound r = bond.Atom.Compound;
         foreach (BaseAtom atom in bond.Atom.Compound.Atoms.ToHashSet())
         {
             Atom.Compound.Atoms.Add(atom);
             atom.Compound = Atom.Compound;
         }
+
+        r.Amount = 0d;
+        r.HomogeneousMixture.Compounds.Remove(r);
     }
     /// <summary>
     /// disconnect with connected bond