d and f BLOCK ELEMENTS

How does the effective nuclear charge experienced by outer electrons change across a transition series due to d electron shielding?

• It decreases
• It remains constant
• It increases
• It fluctuates randomly

What trend is observed in the atomic radii when comparing the first (3d) and second (4d) transition series?

• Radii decrease from 3d to 4d
• Radii remain constant
• Radii increase from 3d to 4d
• Radii fluctuate randomly

What is the shielding effectiveness of f electrons compared to d electrons?

• f electrons provide better shielding than d electrons
• f electrons provide similar shielding to d electrons
• f electrons provide poorer shielding than d electrons
• It depends on the specific element

Which factor is highlighted as important for the occurrence of frequent metal-metal bonding in heavy transition metal compounds?

• Lower atomic radii
• Greater enthalpies of atomisation
• Lower melting points
• Higher electronegativity

Why do metals with high enthalpies of atomisation tend to be noble in their reactions?

• They have low melting points
• High energy required for atomisation contributes to stability and low reactivity
• They readily lose electrons
• They form weak bonds