For the same transition metal ion, the colour of its compounds will depend upon:

• temperature of the reaction

• pressure of the reaction

• nature of ligands or Lewis bases attached to the metal ion

• concentration of the ligands

The 3^rd transitional series contain elements having atomic numbers from:

• 21 to 29

• 21 to 30

• 20 to 30

• 21 to 31

The transition metals mostly are

• paramagnetic

• diamagnetic

• both 'a' and 'b'

• neither diamagnetic nor paramagnetic

Among the oxides, Mn₂O₇ (I) , V₂O₃ (II) , V₂O₅ (III) , CrO (IV) , Cr₂O₃ (V) the basic oxides are :

• I and II

• II and III

• III and IV

• II and IV

The oxygen carrying pigment , oxyhaemocyanin containing two copper ions is diamagnetic , because :

• the two copper ions are in + 1oxidation state

• one copper ion is in + 1oxidation state while other is in + 2 oxidation state

• of the strong antiferromagnetic interactions between two copper ions

• of the ferromagnetic interactions between the two copper ions

616.

Which is not true statement ?

• Ions of d-block elements are coloured due to d-d transition

• Ions of f-block elements are coloured due to f-f transition

• [Sc(H₂O)₆]³⁺ , [Ti(H₂O)₆]⁴⁺ are coloured complexes

• Cu⁺ is colourless ion

The reaction between metallic silver and aqueous NaCN forming a soluble complex occurs in the presence of :

• nitrogen

• oxygen

• helium

• chlorine

Which one is colourless ?

• Co²⁺

• Ni²⁺

• Fe³⁺

• Cu⁺

In first transition series, which element show maximum oxidation states :

• Co

• Mn

• Cr

• Fe

The most paramagenetic is :

• Cr³⁺

• Co²⁺

• Mn²⁺

• Fe²⁺