Which species, has the following ground state electron configuration

Which species, has the following ground state electron configuration: 1s2 2s2 2p6 3s2 3p6 4s0 3d8  (a) Fe+   (b) Ni  (c) Ni2+  (d) Cu2+ 

Which species, has the following ground state electron configuration: 1s2 2s2 2p6 3s2 3p6 4s0 3d8 

(a) Fe+  

(b) Ni 

(c) Ni2+ 

(d) Cu2+ 

The Correct Answer and Explanation is :

The correct answer is (c) Ni²⁺.

Explanation:

1. Given Configuration:
   The electron configuration provided is:
   1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰ 3d⁸. This means the 4s orbital is empty ((4s^0)), and the 3d subshell has 8 electrons ((3d^8)).
2. Understanding Electron Configurations:

• In neutral transition metals, electrons first fill the 4s orbital and then the 3d orbital.
• Upon ionization, electrons are removed first from the 4s orbital before the 3d orbital, because the 4s electrons are higher in energy for transition metals.

1. Analyzing the Choices:

• (a) Fe⁺ (Iron ion):
  Neutral iron ((Fe)) has the configuration (1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶).
  (Fe⁺) would lose one electron, resulting in (1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d⁶), which does not match the given configuration.
• (b) Ni (Nickel):
  Neutral nickel ((Ni)) has the configuration (1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸).
  The 4s orbital is not empty in neutral nickel, so this does not match.
• (c) Ni²⁺ (Nickel ion):
  Neutral nickel ((Ni)) loses 2 electrons to become (Ni²⁺).
  The two electrons are removed from the 4s orbital, leaving (1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰ 3d⁸).
  This matches the given configuration.
• (d) Cu²⁺ (Copper ion):
  Neutral copper ((Cu)) has the configuration (1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d¹⁰).
  Losing two electrons from (Cu) results in (1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰ 3d⁹), not (3d⁸).

1. Conclusion:
   The configuration (1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰ 3d⁸) corresponds to Ni²⁺, making (c) the correct answer.