Question

Which of the following elements belongs to the first inner transition series?

• A. Bk
• B. Pu
• C. Pr
• D. Fm

Hint:

The first inner transition series consists of the lanthanide elements, which are typically found in the f-block of the periodic table. The actinides, on the other hand, are located in the second inner transition series.

Answer 1

The Correct Option is C

Step 1: Understanding the first inner transition series.
The first inner transition series refers to the elements in the Lanthanide series, which are from atomic number 57 (Lanthanum) to atomic number 71 (Lutetium). These elements are also known as the rare earth elements.

Step 2: Analyzing the options.
(A) Bk: This is incorrect. Bk (Berkelium) is part of the actinide series, not the lanthanide series.
(B) Pu: This is incorrect. Pu (Plutonium) also belongs to the actinide series.
(C) Pr: Correct — Pr (Praseodymium) is part of the first inner transition series, belonging to the lanthanides.
(D) Fm: This is incorrect. Fm (Fermium) is part of the actinide series.

Step 3: Conclusion.
The correct answer is (C) Pr, as Praseodymium belongs to the first inner transition series (Lanthanide series).