Transition Metals Flashcards
1
Q
Characteristics of TM:
A
- form complex ions
- formation of colored ions
- variable oxidation states
- catalytic activity
2
Q
Why is Zn not a TM?
A
Zn can only form +2 ions, has a complete d subshell so doesn’t meet TM criteria of incomplete d orbital
3
Q
Complex meaning:
A
a central metal ion surrounded by ligands
4
Q
Ligand:
A
an atom, ion or molecule which can donate a lone electron pair
5
Q
Heterogenous catalyst v homogenous:
A
- hetero: diff state to the reactants
- homo: same state to reactants
6
Q
3 steps in heterogenous catalysis:
A
Adsorbtion:
* reactants adsorb by forming bonds w atoms at the active sites on the surface of catalyst
Bond breaking and making
* as a result bonds in the reactants are weakened and break followed by bond making
Desorbtion
* this in turn weakens bonds betw/ product and catalyst and product leaves
7
Q
Poisoning catalysts:
A
- catalysts can become poisoned by impurities so reduced efficiency
- cost implications
- leaded petrol cant be used in catalytic converter cars since strongly adsorbs onto surface of catalyst
8
Q
autocatalysis:
A
the product of the reaction is the catalyst for the reaction
