Transition Metals Flashcards
Define a transition metal
Stable ions with partially filled d orbitals
What are the characteristics of transition metals?
They have no electrons in the 3d orbitals
Why are zinc and scandium not transition metals?
4s
Define ligands
They have many stable oxidation states
Define complex
Donates a lone pair of electrons to the central atom
What is a co-ordination number?
A central atom or ion surrounded with ligands
What is a monodentate ligand?
Number if co-ordinate bonds to the central atom/ion
State three examples of monodentate ligands
What are the similarities between NH3 and H2O?
Small ligands- H2O, NH3, OH-, CN-
Larger ligands- Cl-
Describe the change in co-ordination number and charge when H2O replaces NH3
No change
Why may a ligand substitution be incomplete?
Change in the co-ordination number
Give an example of a ligand larger than NH3 and H2O
Oxygen forms a co-ordinate bond to iron (II) in Haemoglobin, this enables oxygen to be transported in the blood
What changes when you replace H2O with Cl- ?
It replaces the oxygen co-ordinately bonded to Fe(II) in haemoglobin
Define bidentate ligand
Octahedral complexes that display cis-trans isomerism
State two examples of bidentate ligands
Electrons get excited by heat and radiation so some of the wavelengths of visible light are absorbed and the remaining are transmitted or reflected.