Solubility of Complex Ions: |
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Complex ions: Another way to dissolve partially soluble salts is by forming a complex.
A complex ion is a polyatomic cation or anion composed of a central metal ion to which other groups called ligands are bonded. For [Fe(CN)6]4-(aq) Fe2+ is the central ion and -CN is the ligand The equilibrium constant for creating a complex ion is called a formation constant (Kf) Fe2+(aq) + 6 -CN(aq) ⇔ [Fe(CN)6]4-(aq) Kf = 1 x 1037 Because Kf is very large the equilibrium lies far to the right. Because the complex ion is charged, it is usually water-soluble. This video contains examples, which shows how the formation of a complex can cause an insoluble salt to dissolve. Also, the concentration of a metal cation after complexation is calculated. Here is an index of the other videos in Chapter 20 Solubility Products: https://bit.ly/3feOCxC Here is an index of the entire Video Textbook of Chemistry: https://bit.ly/2TIGQVf |