Which metal ion is likely to form a square planar complex ion with `CN^(-)` ?

Which of the following ion is likely to form white complexes

Which of the following ion is likely to form white complexes

The complex ion [Ni(CN)_4]^(2-) is :

The hybridisation of metal ion in square planar complexes in

Which of the following ions favour square planar geometry ?

Which alkali metal ion forms a stable complex with 18- crown-6

Square planar complexes are generally formed by d^(8) ions with strong field ligands. The crystal field splitting is larger for second and third row transition elements and for more highly charged species. All the complexes having 4d^(8)" and "5d^(8) configuration are mostly square including those with weak field ligands such halide ions. Square planar complexes with coordination number four can show diastereoisomerism. Which of the ions do not form the square planar complexes amongst the following ions ?