Short notes on d and f block elements
D block elements can be found from the third group to the twelth group of the modern periodic table.
d block elements
In d block elements, last electron enters in penultimate shell.
In f block elements, last electron enters in antepenultimate shell.
Cu, Ag, and Au are called coinage elements.
Metals like Pt, Ag, Hg, Cu are known as noble metal.
Physical properties
All d block elements are metals.
These are hard, having metallic lusture, ductile (except Zn,Cd,Hg)
Elements of group 12 are not considered as transition elements because transition element is that, which in elemental state or in any of it's general oxidation state has incompletely filled d orbital.
d block elements have very high tendency to form complexes because of
1. availability of empty orbitals of suitable energy.
2. high charge density.
d block elements have highest tendency to form alloys because of their less reactivity and almost similar size.
Interstitial compounds are formed by trapping of small atoms like hydrogen, carbon, nitrogen, oxygen, boron, etc. in the metallic lattice of d block elements.
• These are neither covalent nor ionic.
• Thes are generally non-schiomrtic.
• These are relatively hard.
• These are chemically inert.
• These maintain electrical conductivity of metal.
d block elements have very good catalytic properties because of there ability to show variable oxidation state and tendency to form complexes.
f block elements
(Inner transition elements)
They are all silverly white soft metals (Eu,Yb - pale yellow). Electropositive in nature.
Most stable Oxidation state for all +3
Ce also shows +4 which act as very good reduction agent.
Size generally decreases across the series Eu - biggest in size, most reactive.
Hydroxides of these are strongly basic in nature, basic strength decreases across the series.
Actinides
All actinides are radioactive.
Only first three elements are naturally occurring.
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