Chemistry - Complete d-block Question with Solution | TestHub
The IUPAC definition of a transition element is that it is an element that has an incomplete d-subshell in either the neutral atom or its ion. Thus the group 12 elements are member of the d-block but are not transition elements.
Chemically soft members of the d-block occurs as sulphide minerals and are partially oxidised to obtain the metal, the more electropositive 'hard' metals occurs as oxides and are extracted by reduction.
Opposite to p-block tend to exist in low oxidation states and favoured by the heavier elements of d-block. Metals on the right of the d-block tend to exist in low oxidation states and form complexes with the ligands. Square-planar complexes are common for the platinum metals and gold in oxidation state that yield d8 electronic condiguration, which include Rh (I), Ir(I), Pd(II), Pt(II) and Au(III).
The most distinctive features/properties of transition metal complex is their wide range of colours. The crystal field theory attributes the colour of the coordination compounds to d-d transition of the electron. It is important to note that (a) in absence of ligand, crystal field splitting does not occur and hence the substance is colourless ; (b) the type of ligand also influences the colour of the complexes.
Which of the following has hydridisation and is diamagnetic in nature ?
(I) (II) (III)
(IV) (V)
Options:
Answer:
Solution:
(I)
co is strong field ligand so complex is diamagnetic and tetrahedral. hybridisation
(ii)
DMGH is a chelating lignad so comples is diamagnetic and square planar.
(III)
configuration has greater CFSE, so complex is diamagnetic and square planar.
No empty d-orbital is available for dsp2 hybridisation and is weak field ligand so complex tetrahedral and diamagnetic.
(V)
configuration has greater CFSE, so complex is diamagnetic and square planar.