Transition Metals Flashcards
What are transition metals said to be? (Block)
D-block elements
Give the definition of transition metals
Transition metals form at least one ion with a partially filled d-sub shell
The d orbitals are filled according to the Aufbau principle, with the exception of what 2 elements?
Copper
Chromium
What are half filled d orbitals said to be and why?
More stable due to the equal distribution of charge around the atom
What are the 3 d5 configuration anomalies ?
Chromium
Molybdenum
Tungsten
What are the 2 d10 configuration anomalies?
Copper and silver
What can transition metals exhibit ?
Variable valency - the atoms can lose the 4s electrons and some or all of the 3d electrons
What do transition metals have?
Coloured ions
Why are Sc3+ and Zn2+ not considered transition metals?
Because they do not have a partially filled d-subshell
What does a transition metal complex consist of ?
A central transition metal ion surrounded by ligands
What are ligands ?
Electron rich (have non-bonding pairs of electrons) or are negatively charged ions
What are ligands said to be ?
Neutral or anionic non-metal species
What do ligands act as?
Electron donors to the transition metal ion
What do ligands form bonds with?
The transition metal ions by donating non-bonding electrons to empty d-orbitals on the central TM ion
The Ligand donates both electrons in the new bond. What is this bond called?
A dative covalent bond (represented by an arrow)
How may ligands be attached to the metal ion?
By a single atom (monodentate) or bound to the metal through two or more atoms (bidentate, tridentate)
Give 2 examples of monodentate ligands ?
Ammonia
Water
Give 2 examples of bidentate ligands ?
Ethanedioate ion
1,2- diaminoethane
Give an example of a hexadentate ligand ?
EDTA4-
What is the mole ratio of the metal ion to EDTA ?
1:1
What is the cooridination number of the ion?
The number of BONDS from the Ligand to the central ion
What are coordination number and geometry determined by?
A combination of metal ion size and Ligand size
What shape are complexes with coordination number 4 typically?
Tetrahedral or square planar
What shows the coordination number of the TM ion?
The chemical formulae
What shape are complexes with coordination number 6 typically?
Octahedral
