Transition metals and complex ions 208-209

Question 1

Define the term complex ion.

Answer 1

A complex ion is a transition metal ion bonded to one or more ligands by coordinate bonds.

Question 2

Define the term ligand.

Answer 2

A ligand is a molecule or ion that can donate a pair of electrons with the transition metal ion to form a coordinate bond.

Question 3

Define the term coordination number.

Answer 3

The coordination number is the total number of coordinate bonds formed between a central metal ion and its ligands.

Question 4

Give the formula and charge for the following ligands:

• Water
• Ammonia
• Thiocyanate
• Cyanide
• Chloride
• Hydroxide

Answer 4

Water: :OH₂ , Charge: neutral ligand.

Ammonia: :NH_3,Charge: neutral ligand

Thiocyanate: :SCN^- , Charge: -1

Cyanide: :CN^- , Charge: -1

Chloride: :Cl^- , Charge: -1

Hydroxide: :OH^- , Charge: -1

Question 5

Describe the octahedral shapes/angles of the complex ions.

Answer 5

In an octahedral complex, four of the ligands are in the same plane, one ligand is above the plane and the remaining ligand are below the plane. All bond angles are 90*.

Octahedral complexes have six coordinate bonds attached to the central ion.