Paramagnetic: A material is said to be paramagnetic substance when it is attracted by a magnet when kept in a magnetic field. Paramagnetism occurs due to the presence of unpaired electrons.
Ferromagnetic: A material is said to be ferromagnetic substance when it exhibits permanent magnetism even when the magnetic field is removed.
The number of unpaired electrons present in bivalent ions of transition metal series from
Z = 22 to Z = 29 is given below:
From this it is clear that the paramagnetism character of bivalent ion of transition series varies as Mn2+ > Cr2+ = Fe2+ > V2+ = Co2+ > Ti2+ = Ni2+ > Cu2+
Describe the general characteristics of the transition elements with special reference to their tendency to:
(i) Exhibit paramagnetism.
(ii) Form complex compounds.
(iii) Their catalytic behaviour.
Assign reasons for the following:
The enthalpies of atomisation of transition metals are high.
How is the variability in the oxidation states of transition metals different from that of the nontransition metals? Illustrate with examples.
In what way are the observed oxidation states of the lanthanides related to their electronic configurations?
