d and f BLOCK ELEMENTS

Why is the hardness of interstitial compounds significantly higher than that of the pure metals?

• They are purely ionic
• They contain only metallic bonds
• They have low melting points
• The trapped atoms cause lattice distortion, creating internal stresses that resist deformation

What is the term used for alloys where the atoms are distributed randomly within a single crystal lattice?

• Heterogeneous mixtures
• Intermetallic compounds
• Homogeneous solid solutions
• Mechanical mixtures

Which property of transition metals is NOT directly related to their catalytic activity mentioned in the text?

• Ability to adopt multiple oxidation states
• Ability to form complexes
• High density
• Presence of d-orbitals

What is the main component of the alloy bronze according to the text?

• Zinc
• Lead
• Tin
• Copper

What is the main component of the alloy brass according to the text?

• Zinc
• Lead
• Tin
• Copper