d and f BLOCK ELEMENTS

How does the presence of unpaired electrons relate to the magnetic properties of transition metal complexes?

• Unpaired electrons always make compounds diamagnetic.
• More unpaired electrons decrease paramagnetism.
• Unpaired electrons lead to paramagnetism, while paired electrons lead to diamagnetism.
• Paired electrons increase the magnetic moment.

Why are interstitial compounds formed primarily by transition metals?

• They are more reactive than other metals.
• They have larger atomic radii.
• Their crystal structures possess suitable interstitial voids for small atoms.
• They have lower melting points.

What is a consequence of the similar sizes of Zr/Hf and Nb/Ta pairs?

• It increases their reactivity.
• It makes their compounds more colored.
• It makes the separation of these elements very difficult.
• It decreases their melting points.

What is the role of transition metals in catalysis primarily attributed to?

• Their high melting points
• Their ability to form ionic bonds only
• Their ability to adopt multiple oxidation states and form temporary bonds with reactants.
• Their large atomic radii

Why do transition metal complexes often exhibit paramagnetism?

• They always have paired electrons.
• They contain only s-electrons.
• They frequently contain unpaired electrons in their d-orbitals.
• They lack d-electrons.