Respuesta :

Answer:

D. Cr

Explanation:

In order to determine which atom has at least one electron in its d orbital, we have to write their theoretical electron configurations.

  • ₁₂Mg 1s² 2s² 2p⁶ 3s²
  • ₁₉K 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
  • ₁₆S 1s² 2s² 2p⁶ 3s² 3p⁴
  • ₂₄Cr 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁴

Cr has 4 electrons in d orbitals. Cr belongs to the d-block in the periodic table.