Tranition metals Flashcards
What are transition metals
D block elements that have an ion with an incomplete d subshell.
Electron configuration of chromium
3d5 4s1
Electron configuration of copper
3d10 4s1
Transition elements form compounds in which they have different oxidation states
For example Iron forms two different chlorides, Iron (2) chloride Fe2Cl and Iron (3) chloride Fe3Cl.
Transition elements form coloured compounds
Potassium dichromate is bright orange and Nickel (2) sulfate is green.
Transition elements and their compounds can act as a catalyst
Iron is used in the haber process to make ammonia from nitrogen and hydrogen. Nickel is used as a catalyst in the hydrogenation of alkenes, for example making margarine.
A ligand
A molecule or ion that donates a pair of electrons to a central metal ion to form a coordinate bond (dative covalent bond)
A dative covalent bond or coordinate bond
A special kind of covalent bond, formed when one of the bonded atoms provides both of the electrons in a shared pair
Coordinate number
Indicates the number of coordinate bonds attached to the central metal ion
Example of a complex ion
[Cr(H2O)6] 2+
Monodentate ligand
Only donates one pair of electrons
Bidante ligand
Donates two pairs of elecrons to the central metal ion.
Octohedral complex ion
Has a coordinate number of 6, bond angle of ninety degrees
Tetrahedral complex ion
Most common shape for a complex ion with a coordinate number of four, bond angle is 109.5
Square planar complex ion
Bond angle of ninety degrees, occurs with 8d elements ie platinum, gold and palladium