3.4 The Transition Metals Flashcards
What is a transition metal?
An element which from at least one stable ion with a partially filled d sub shell.
Why is zinc not classified as a transition metal?
The only ion formed by Zn is the 2+ ions which has a full 3d sub shell.
What are some characteristics of transition metals?
Transition elements can exhibit more than one oxidation state in compounds/complexes.
Transition elements form complex ions.
Transition elements form coloured compounds/complexes.
Transition elements and their compounds/complexes can act as catalysts in many reactions.
Compounds of transition elements can exhibit magnetic properties.
What oxidation state do all transition metals exhibit when the 4s electrons are removed?
+2
How is the maximum oxidation state exhibited by a transition metal found?
By the sum of the number of 4s and 3d electrons.
Why is there more than one oxidation state?
The 4s and 3d sub shells are close in energy and there are no big jumps in the successive ionisation energies when the 4s and 3d electrons are removed.
What is a complex ion?
A central trasntion metal ion surrounded by ligands.
What is a ligand?
Negative ions or natural molecules which use lone pairs of electrons to bond to a transition metal ion to form a complex ion.
What must a ligand possess?
A lone pair of electrons.
When are coordinate bonds formed?
Between the ligand and the transition metal ion - the ligand donates a pair of electrons to the transition metal ion.
How can the total charge on a complex ion be worked out?
From the charges on the ligands an the oxidation state of the transition metal.
What are some examples of neutral ligands?
H20
NH3
CO
What are some examples of negative charged ions?
Cl-
CN-
OH-
What are paramagnetic substances?
Substances attached by a magnetic field - caused by the presence of unpaired electrons.
What are diamagnetic substances?
Repelled slightly by a magnetic field - caused by presence of paired electrons.
