Transition Metals Flashcards
(17 cards)
What is a transition metal?
One which forms one or more stable ions which have incompletely filled d orbitals.
Why isn’t Zinc a Transition Metal?
It has a full d-orbital in both it’s elemental and ionic state
Name four features of Transition Metals
- Coloured
- Form Complexes
- Catalytic
- Variable Oxidation States
What is a Complex Ion?
An Ion where the Coordination Number is Greater than the Oxidation State
Why do Transition Metals make good catalysts?
- Ability to change Oxidation States
- Able to make bonds with the reactants using the partly filled d-orbitals
Why do Transition Metals exhibit colour?
- d-orbital energy level raised when ligands attatch
- Electron from lower energy level promoted to the higher energy level
- When light is passed through the solution, some of the wavelengths are absorbed
- Complementary colour to that absorbed is reflected
- Different Ligand means different energy level
What shape is [Cu(H2O)6]2+ ?
Octahedral
What shape is [CuCl4]2-
Tetrahedral
What is a ligand?
A molecule with a lone pair
What colour is [Cu(H2O)6]2+
Blue
What colour is [Cu(NH3)4(H2O)6]2+
Royal Blue
What colour is [CuCl4]<span>2-</span>
Yellow-Green
What is a bidentate ligand?
A molecule which can form two coordinate bonds
e.g. H2N-CH2-CH2-NH2
Give an example of a polydentate ligand
EDTA
Give a use of any transition metal in biological systems
- Iron, Haemaglobin in blood
- Cobalt, Vitamin B12
Which electrons are lost first? 4s or 3d
4s
What is strange about the electron configuration of Cu and Cr
They have an unpaired electron in the 4s shell, so they can have a full (in the case of Cu) or half full (Cr) d orbital
