Topic 15 - Transition Metals Flashcards
Where in the periodic table are transition metals found?
d - block
What is a transition metal?
d - block elements that form one or more stable ions with incompletely filled d-orbitals
Between what elements are d-block elements?
Sc to Zn
Between what elements are transition metals?
Ti to Cu
Why aren’t Sc and Zn transition metals?
Their ions do not form incomplete d-orbitals
What are the characteristics of transition metals?
Hard solids.
High melting and boiling temperatures.
Can act as a catalyst.
Form coloured ions and compounds.
Form ions with variable oxidation states.
What is the d-orbital?
A double dumbbell shape made of 5 orbitals.
What are the exceptions to the normal filling order?
Chromium and Copper - they only have 1 electron in the 4s shell.
How can electronic configurations be abreviated?
By using the EC of Ar.
e.g. titanium would be [Ar] 4s2 3d2
What is the electronic configuration of Ar?
1s2 2s2 2p6 3s2 3p6
How many electrons are there in [Ar]?
18
What is a ligand?
A molecule or ion that donates a pair of electrons to the central metal ion to make a dative covalent bond.
What is a complex ion?
A transition metal with a ligand attached by a dative covalent bond.
What is a monodentate ligand?
A molecule/ion that has one atom that donates a pair of electrons to the central metal ion in a dative covalent bond.
What is an example of a monodentate ligand?
H2O
What is the co-ordination number for a monodentate ligannd?
6
How does H2O act as a ligand?
The O donates a pair of electrons for a dative covelant bond. 6 water molecules are needed for a full hydration. e.g. [Cu(H2O)6]2+
What is a bidentate ligand?
A molecule/ion that has two atoms that donate a pair of electrons to the central metal Ion in a dative covalent bond.
What are examples of bidentate ligands?
Diaminoethane (en)
H2N: - CH2 - CH2 - :NH2
or Ethane Dioate ions
-O - C=O - C=O - O-
What is the co-ordination number of a bidentate ligand?
3.
as each molecule has two places that can donate a pair of electrons to the CMI.
How does diaminoethane (en) attach to a CMI?
The nitrogen’s donate their lone pair of electrons to the CMI. As there are two nitrogens in the molecule there are two dative covalent bonds made per molecule.
[Cu(en)3]+2
How do ethane dioate ions attach to the CMI?
The oxygens (O- not =O) donate their lone pair of electrons to the CMI. As there are two oxygens in the molecule there are two dative covalent bonds made per molecule.
[Cu(C2O4)3]-4
What is a multidentate ligand?
A molecule/ion that has more than two atoms that can donate a pair of electrons to a central metal ion in a dative covalent bond.
What is an example of a multidentate ligand?
EDTA-4
(Ethylenediaminetetraacetic acid)