Chemistry

Question Analysis
This question tests the student's understanding of electron configurations and the order of electron loss in ions.

Key Concept Explanation
The electron configuration of a neutral copper atom (Cu) is [Ar] 4s¹ 3d¹⁰. When forming Cu²⁺, the 4s electron is lost first, followed by one 3d electron, resulting in the configuration [Ar] 4s⁰ 3d⁹.

Step-by-step Solution
1. Write the electron configuration of neutral Cu: [Ar] 4s¹ 3d¹⁰.
2. Form Cu²⁺ by removing 2 electrons: first the 4s electron, then one 3d electron.
3. The res...