d and f BLOCK ELEMENTS

Which of the following oxidation states is NOT listed for Uranium (U) in Table 4.11?

• +3
• +4
• +6
• +7

What is a significant difference in the chemical behavior of 5f electrons compared to 4f electrons?

• 5f electrons are more stable
• 5f electrons are always paired
• 5f electrons participate more in bonding
• 5f electrons have lower energy

For which actinoid does the formal filling of the 5f subshell begin?

• Actinium (Ac)
• Thorium (Th)
• Protactinium (Pa)
• Uranium (U)

Which of the following electronic configurations is attributed to Curium (Cm)?

• [Rn] 5f⁶ 7s²
• [Rn] 5f⁸ 7s²
• [Rn] 5f⁷ 7s²
• [Rn] 5f⁷ 6d¹ 7s²

Which actinoid has the shortest listed half-life according to the provided text?

• Uranium
• Plutonium
• Lawrencium
• Neptunium