d & f Block Elements Flashcards
Zn Cd Hg are not typical d block elements because
They have completely filled d orbitals in their ground state as well da in their common oxidation state.
d block includes the groups
3-12
General E.C of d block elements is
(n-1)d^1-10 ns0-2
Which transition metals do not have a typical metallic structure at normal temp
Zn Cd Hg Mn
Trend of enthalpy of atomisation and mp in d block
Rises upto d5 and falls regularly as atomic number increases
Except anamolous Mn and Tc
What is lanthanides contraction?
Filling of 4f electron before 5d results in a regular decrease in atomic radii
Hence, 4d & 5f series exhibit similar radii and properties
The transition metal which does not show variable o.s
Sc
Transition metals which exhibit o.s of +8
Rh and Os
Why higher o.s are stable with O and F
Due to high oxidising power of F &O
Tendency to form divalent cations decreases across the series because of
Increase in reduction potential from left to right
Strongest oxidising agents in aq solutions are
Mn3+ and Co3+
Frequency of light absorbed is determined by
Nature of ligand
Size of metal ion
Oxidation state of metal
Colour may be due to
d-d transition Charge transfer spectra Eg:-(MnO4- is pink) Polarisation Eg:-(AgBr AgI)
Transition metals show catalytic properties because of their ability to
Form complex compounds
Adopt multiple oxidation states
Fe is used to catalyse
Haber process
PdCl2 catalyses
Wacker process
Adams catalyst is
Pt/PtO2
Lowest melting point metals among transition metals belong to
Group 12
Most abundant transition metal is
Iron
All metals form ionic metal oxides except
Sc
Nature of higher oxides is predominantly
Acidic
Cr2O3 and V2O5 are
Amphoteric oxides
CrO is basic
Chromite is
FeCr2O4
Potassium dichromate is used in
Leather industry and in preparation of azo compounds