Comment on the statement that the element of the first transition series possess many properties different those of heavier transition elements.

Comment on the statement that the element of the first transition seri

1.	Comment on the statement that the element of the first transition series possess many properties different those of heavier transition elements.
Answer» Solution :The given statement is true as explained below `:` (i) ATOMIC radii of the heavier transition elements ( 4d and 5d series ) are larger than those of the corresponding elements of the FIRST transitionseries though those of 4d and 5d series are very CLOSE to each other. (ii) For first transition series, `+2` and `+3` oxidationstates are more common whereas for heavier transition elements, higher oxidation states are more common( as DISCUSSED in Question) (iii) Melting and boiling POINTS of heavier transition elements are greater thanthose of the first transition series due tostronger intermetallic bonding ( M-M bonding) . (iv) Ionization enthalpiesof 5d series are higher than the corresponding elements of 3d and 4d series. (vi ) The elements of the firsttransition series form low spin or high spin complexesdepending upon the strength of the ligand field.However, the heavier transition elements form low spin complexes irrespective of the strength of the ligand field.