Write the ground-state electron configuration of a europium atom. A)[Xe]5d⁷6s² B)[Xe]4f²5d⁵6s² C)[Xe]4f⁹ D)[Xe]4f⁷6s² E)[Xe]4f⁵5d²6s²

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Quizplus · Accepted Answer

The electron configuration of europium can be determined by looking at the position of the element on the periodic table. Europium is in the f-block, specifically in the lanthanide series, and therefore has its valence electrons in the 4f subshell. The ground-state electron configuration of europium can be represented as [Xe]4f7 6s2. However, in the multiple choice options, this configuration is written using the noble gas shorthand notation, where Xe represents the electron configuration of the noble gas xenon (which is in the same row as europium). Option D is the closest to this notation and correctly writes the electron configuration as [Xe]4f7 5d0 6s2  which indicates that 5d subshell is still empty.

Write the Ground-State Electron Configuration of a Europium Atom