Correct statements about transition metals are that they:

Options

A. form complex
B. show variable oxidation states
C. show magnetic properties
D. do not from coloured compounds

Answer

ABC

Explanation

the great tendency of transition material ion to form complex is due ,(i) small size to the atoms and ions(ii) high nuclear charge and (iii) availability of vacant d-suitable energy to accept lone pair of electrons donates by ligands.
(B) The existence of the transition element in different oxidation state is due to the participation of inner `(n-1)` d-electrons in addition to outer ns-electrons because , the energies of the ns and (n-1) d-sub-shells are nearly same.
(C ) The transition metals show magnetic properties due to presence of number of unpaired electrons in d-orbital.
(D) Most the transition metal ion are coloured, because they have unpaired electrons which can undergo d-d transition in presence of ligands.