Question

Which among the following lanthanoids shows only +3 oxidation state?

• A. Terbium
• B. Gadolinium
• C. Neodymium
• D. Cerium

Hint:

Many lanthanoids exhibit the +3 oxidation state, but a few can show higher or lower oxidation states under specific conditions, like cerium and neodymium.

Answer 1

The Correct Option is B

Step 1: Understanding the oxidation states of lanthanoids.
Lanthanoids typically exhibit a +3 oxidation state, but some elements like cerium can also show +4 oxidation states. Gadolinium, however, exclusively exhibits the +3 oxidation state.

Step 2: Analyzing the options.
(A) Terbium: Terbium primarily exhibits the +3 oxidation state, though it can also exist in other states.
(B) Gadolinium: Gadolinium exclusively shows the +3 oxidation state.
(C) Neodymium: Neodymium generally shows +3 oxidation state but can also show +2 in some compounds.
(D) Cerium: Cerium can show both +3 and +4 oxidation states.

Step 3: Conclusion.
The correct answer is (B) Gadolinium, as it only exhibits the +3 oxidation state.