Which of the following is the most specific classification for the element europium?

• A. Transition metal
• B. Lanthanide
• C. Actinide
• D. Alkali metal

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the classification categories given: Transition metals, Lanthanides, Actinides, and Alkali metals. These are groups or series in the periodic table that classify elements based on their properties and electron configurations.
2. Step 2: Identify europium's position in the periodic table. Europium has the atomic number 63 and is located in the f-block of the periodic table, which contains the lanthanide series.
3. Step 3: Recall that lanthanides are the 15 elements from atomic numbers 57 (lanthanum) to 71 (lutetium), characterized by filling of the 4f electron orbitals.
4. Step 4: Recognize that transition metals are d-block elements, typically from groups 3 to 12, and europium is not in this block, so it is not a transition metal.
5. Step 5: Conclude that europium is most specifically classified as a lanthanide because it belongs to the f-block lanthanide series, making 'Lanthanide' the most specific and correct classification.