d and f BLOCK ELEMENTS

What is the ground state electronic configuration of Hafnium (Hf, Z=72)?

• [Xe] 4f¹⁴ 5d⁴
• [Xe] 4f¹⁴ 5d¹ 6s³
• [Xe] 4f¹⁴ 5d³ 6s¹
• [Xe] 4f¹⁴ 5d² 6s²

What is the ground state electronic configuration of Zirconium (Zr, Z=40)?

• [Kr] 4d⁴
• [Kr] 4d¹ 5s³
• [Kr] 4d³ 5s¹
• [Kr] 4d² 5s²

What is the ground state electronic configuration of Yttrium (Y, Z=39)?

• [Kr] 4d³
• [Kr] 4d² 5s¹
• [Kr] 4d⁰ 5s³
• [Kr] 4d¹ 5s²

Why are transition metal compounds often good catalysts?

• They are always in the +1 oxidation state
• They are highly reactive and consume reactants quickly
• They can adopt multiple oxidation states and form temporary bonds with reactants.
• They only work at very high temperatures

Which of the following is an example of a transition metal that exhibits the highest number of common oxidation states?

• Iron (Fe)
• Chromium (Cr)
• Vanadium (V)
• Manganese (Mn)