Write the ground‑state electron configuration for the element having the configuration $[Xe]4f^{14}5d^{1}6s^2$. Identify the element and state whether it belongs to the d‑block or f‑block of the periodic table.

Step-by-step solution

1. Count the total electrons: $[Xe]$ contributes 54, $4f^{14}$ adds 14, $5d^1$ adds 1, and $6s^2$ adds 2, giving 54+14+1+2 = 71 electrons.
2. An atomic number of 71 corresponds to the element Lutetium (Lu).
3. Lutetium has the configuration ending in $5d^{1}6s^2$, placing the outermost electron in a d orbital.
4. Hence Lu is considered a d‑block element (group 3) even though it follows the lanthanide series.

Concept tested: identifying element from electron configuration

Published 2 September 2026 · Last updated 16 September 2026 · How this solution was prepared and checked

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