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Configurations of the common ions

Configurations of the common ions

Point 7 of 11 — Lesson 1: First Transition Series, Electronic Configurations and Economic SignificanceQuestion bank: 1 questions (1 with pictures)

07 Configurations of the common ions

  • In forming positive ions the atom loses the 4s electrons first, and only then 3d electrons (the 4s and 3d sublevels are close in energy, and once the 3d sublevel starts to fill, the 4s electrons are the outer, easiest to remove).
  • Examples:
1Sc³⁺
Configuration
  • [Ar] (3d⁰)
Remarks
  • has the stable argon structure; the reason why Sc forms only +3 and never Sc²⁺ (losing only the two 4s electrons would leave 3d¹, which is easily lost)
2Ti⁴⁺
Configuration
  • [Ar] 3d⁰
Remarks
  • in TiO₂
3V⁵⁺
Configuration
  • [Ar] 3d⁰
Remarks
  • in V₂O₅
4Cr³⁺
Configuration
  • [Ar] 3d³
Remarks
  • 3 unpaired electrons
5Mn²⁺
Configuration
  • [Ar] 3d⁵
Remarks
  • half-filled, stable
6Fe²⁺
Configuration
  • [Ar] 3d⁶
Remarks
  • 4 unpaired electrons
7Fe³⁺
Configuration
  • [Ar] 3d⁵
Remarks
  • half-filled, 5 unpaired electrons
8Co²⁺
Configuration
  • [Ar] 3d⁷
Remarks
  • 3 unpaired electrons
9Ni²⁺
Configuration
  • [Ar] 3d⁸
Remarks
  • 2 unpaired electrons
10Cu⁺
Configuration
  • [Ar] 3d¹⁰
Remarks
  • filled sublevel
11Cu²⁺
Configuration
  • [Ar] 3d⁹
Remarks
  • 1 unpaired electron (so Cu is a transition element)
12Zn²⁺
Configuration
  • [Ar] 3d¹⁰
Remarks
  • filled sublevel

📝 Question bank for this point

1 questions linked to this point only, 1 of them with pictures.