d and f BLOCK ELEMENTS

Which of the following best describes the general trend in ionization enthalpies across the Lanthanoid series?

• They generally increase, but with some irregularities due to f-subshell stability
• They generally decrease across the series
• They remain constant across the series
• They decrease sharply and then increase

Why is the reaction rate mentioned in the context of Ce⁴⁺ being a good analytical reagent?

• To explain why its strong oxidizing potential doesn't prevent its practical use
• To indicate that Ce⁴⁺ reacts instantly with all analytes
• To show that Ce⁴⁺ is safe to handle
• To prove that Ce⁴⁺ cannot oxidize water

Which of the following best summarizes the relationship between the lanthanoid contraction and the periodic table?

• It makes properties of third-row transition elements similar to second-row elements
• It makes Lanthanoids behave like transition metals
• It increases the reactivity of first-row transition elements
• It eliminates the difference between metals and non-metals

What is the primary difference in the electronic configurations of Tb³⁺ and Tb⁴⁺ ions?

• Tb³⁺ has a 4f⁸ configuration, while Tb⁴⁺ has a 4f⁷ configuration
• Tb³⁺ has a 4f⁷ configuration, while Tb⁴⁺ has a 4f⁸ configuration
• Tb³⁺ has a 4f⁹ configuration, while Tb⁴⁺ has a 4f⁸ configuration
• Tb³⁺ has a 4f⁸ configuration, while Tb⁴⁺ has a 5d¹ configuration

What is the primary difference in the electronic configurations of Yb²⁺ and Yb³⁺ ions?

• Yb²⁺ has a 4f¹⁴ configuration, while Yb³⁺ has a 4f¹³ configuration
• Yb²⁺ has a 4f¹³ configuration, while Yb³⁺ has a 4f¹⁴ configuration
• Yb²⁺ has a 4f¹² configuration, while Yb³⁺ has a 4f¹¹ configuration
• Yb²⁺ has a 4f¹⁴ configuration, while Yb³⁺ has a 5d¹ configuration