Chemistry - Complete d-block Question with Solution | TestHub

Here statement (3) is not true as Zn, Cd and Hg are not regarded transition metals, because the neutral atoms as well as stable ions have fully-filled d-orbitals.
Statements (1), (2) and (4) are true as transition metals have similar atomic sized, therefore, in the crystal lattice, one transition metals atoms can be easily replaced by the atoms of another transition metal to form alloy. They can easily form complexes, because they form small highly charged cations, which have vacant orbitals of suitable energy to accept electron pairs donated by ligands.
As the sum of first four ionization energies of Pt is less than the sum of first four ionization energies of Ni, so${\mathrm{K}}_2\left[\mathrm{P}\mathrm{t}\mathrm{C}{\mathrm{l}}_6\right]$is more stable than the corresponding nickel compound.