transition metals Flashcards
what is a transition metal?
a d block element that is able to form at least one ion with an incomplete d sub shell.
What are four useful properties of TM?
The can form complex ions.
They have variable oxidation states.
The are colourful compounds.
They are good catalysts
Give three physical properties of transition metals.
They are malleable.
High melting/boiling point.
High density.
Why are Sc and Zn not examples of TM?
Despite being in the d sub shell they don’t form ions with an incomplete sub shells.
The 4s sub shell __ and __ before the 3d sub shell. Unless __ or __.
fills and empties
copper or chromium
How can TM easily from ions with different oxidation states?
1st and 2nd ionisation energies are low so it’s easy to lose 4s and 3d electrons.
which oxidation state is most common at the start of the d block?
+3 as it’s easier to lose electrons.
Which oxidation state is most common at the end of the d block?
+2
How does Cu2+ appear blue?
It absorbs red light and reflects blue light so appears blue.
How does Zn2+ appear colourless?
It reflects all light.
How do TM make good catalysts?
They have different oxidation states. Ions have incomplete d such shell available for electrons.
define a homogenous catalyst
Has the same state as the reactants
define heterogeneous catalyst
Different state to the reactants
What is a coordinate bond?
A dative covalent bond when positive metal ion accepts electron pairs from other ions or molecules.
What is a ligand? give examples
A molecule or ion that forms a coordinate bond/dative covalent bond with a central TM ion. It contains a lone pair of electrons. ie water, ammonia, chloride ion or cyanide ion.
