15.6 - Formation of Complex Ions

• what's a ligand?

  a species that uses a lone pair of electrons to form a dative covalent bond wiht the central metal ion
• what's a complex?

  species containing a metal ion joined to ligands
• what's a complex ion?

  a complex with an overall charge
• what's the coordination number?

  number of dative covalent bonds in a complex
• what affects the coordination number?

  size of central atom or ion or ligand

  the smaller the ionic radii the less dative covalent bonds as ligands are closer together so more repulsion
• what is observed when a complex ion forms?

  colour change or insoluble solid dissolving