For the following X ions, provide condensed ground-state electron configurations and indicate which ions have electron configurations identical to inert gases.
(a) Sc³⁺
(b) Li⁺
(c) O²⁻
(d) F⁻
(e) Ca²⁺
(f) V²⁺

• A. Sc³⁺ = [Ar] 3d¹
  Li⁺ = [He], Noble gas
  O²⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  F⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  V²⁺ = [Ar] 3d³
• B. Sc³⁺ = [Ar], Noble gas
  Li⁺ = [He], Noble gas
  O²⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  F⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  V²⁺ = [Ar] 3d³
• C. Sc³⁺ = [Ar], Noble gas
  Li⁺ = [He], Noble gas
  O²⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  F⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  V²⁺ = [Ar] 3d¹
• D. Sc³⁺ = [Ar]4s¹, Noble gas
  Li⁺ = [He], Noble gas
  O²⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  F⁻ = [He] 2s² 2p⁶ = [Ne], Noble gas
  V²⁺ = [Ar] 3d³

Answer: (B)