d and f BLOCK ELEMENTS

What is the general trend observed in the ionic character of transition metal oxides as the oxidation number of the metal increases?

• Ionic character increases
• Ionic character remains constant
• Ionic character decreases then increases
• Ionic character decreases

Which of the following oxides is known to be a covalent green oil?

• CrO3
• V2O5
• Mn2O7
• TiO2

What is the definition of 'disproportionation' of an oxidation state?

• A process where an element gains electrons
• A process where an element loses electrons
• A process where a single oxidation state simultaneously undergoes oxidation and reduction to form two different oxidation states
• A process where two oxidation states combine to form one

What is the primary reason Cu+ ion is not stable in aqueous solutions?

• It is highly soluble
• It undergoes disproportionation
• It is a strong oxidizing agent
• It forms stable complexes

Why do interstitial compounds like Fe₃H retain metallic conductivity?

• The interstitial atoms donate electrons
• They form ionic crystals
• The delocalized electrons from the host metal framework remain mobile
• They have a simple molecular structure