Complex Ions
Learning Outcomes
What are we learning?
We are learning about Complex Ions and how to
name them.
Why are we learning it?
To understand the different reactions that
transition elements undergo.
How are we going to learn it?
Completing tutorial on naming complex ions and
then conducting an activity on naming.
What have we learnt so far?
1. Properties of Transition elements
2. Electronic configuration
3. Oxidation numbers & formation of coloured
compounds
4. Redox Equations
5. Precipitation reactions
ADVICE: Use this List to now make a revision page on
these topics. Condense your notes!
What’s next?
COMPLEX IONS AND LIGAND FORMATION
What is a Complex Ion?
A property of transition metals is their ability to form
complex ions
Complex ion:Central metal ion is surrounded by ligands
Ligand: Molecule / ion which donates a pair of
electrons forming a coordinate bond (dative bond)
Coordinate bond: One of the bonded atoms has
provided both electrons for the covalent bond
An example:
• Fe 2+ is the metal ion.
• Ligands are the water molecules.
• Coordination number is the number of coordinate bonds to the central metal
ion = 6.
• Square brackets groups the species and the overall charge is written outside
the brackets.
• Overall charge is the sum of the charges of the metal ion and the ligands (if
the ligands have a charge
Naming Complex Ions 1
Naming the Ligand
Naming Complex Ions 2
Naming the amount
of Ligand
Naming Complex Ions 3
Naming the transition metal:
For positively charged complex ions
A positively charged complex ion is called a
cationic complex. A cation is a positively
charged ion.
Naming Complex Ions 3
Naming the transition metal
• For negatively charged
complex ions
• A negatively charged complex
ion is called an anionic
complex. An anion is a
negatively charged ion.
• The ending is changed to -ate.
Naming Complex Ions 4
Writing the charge:
Always in brackets on the end e.g:
Tetrachlorocuprate(II)
Going back to our example . . .
What’s the name?
And finally: How to write the formula
Tetrachlorocuprate(II)
Hexaaquacopper(II)
Lets break it down:
Lets break it down:
Tetra =
Chloro =
Cuprate =
(II) =
Hexa =
Aqua =
Copper =
(II)
[CuCl4]2-
[Cu(H2O)6]2+
Homework: (in addition to questions
in green book)
Using what you know about the names and
formulae of Complex Ions. Research shapes
and types of bonding.
Poster format would be best, as it can then be
used for revision.