Cu²⁺ ion
[Ar] 3d⁹. 1 unpaired electron, paramagnetic.
Element or ion
Type a symbol, a name or an atomic number, add a charge such as Fe3+ or Cl-, or tap an element in the table. Orbitals fill from m = −l up, spin +½ first.
Cu2+Copper ion, 27 electrons
[Ar] 3d9
In full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹. Cu loses 4s¹ then 3d¹
Cu loses 4s¹ then 3d¹
- Blockd block
- Period4
- Group11
- Outer shell17
- Unpaired1
- MagneticPara
Last electron 3d
- n3shell
- l2d subshell
- m+1orbital
- s−½spin down
Step by step
- Copper has 29 electrons: [Ar] 3d¹⁰ 4s¹.
- The ion has 2 fewer, 27 electrons. Remove them from the highest n first.
- Cu loses 4s¹ then 3d¹.
- Cu²⁺ ion: [Ar] 3d⁹, in full 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹.
Cu²⁺ ion: the numbers
| Atomic number | 29 |
|---|---|
| Electrons | 27 |
| Period | 4 |
| Group | 11 |
| Block | d block |
| Electrons in the outer shell | 17 |
| Unpaired electrons | 1 |
| Magnetic | paramagnetic |
| Last electron | 3d: n = 3, l = 2, m = +1, s = −1/2 |
Cu²⁺ ion: quick answers
What is the electronic configuration of Cu²⁺?
Cu²⁺ has 27 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹, or [Ar] 3d⁹. Cu loses 4s¹ then 3d¹.
How many unpaired electrons are there in Cu²⁺?
Cu²⁺ has 1 unpaired electron, so it is paramagnetic.
Why does Cu lose its outer electrons first?
Electrons leave from the highest n first. The 4s level fills before 3d, but once 3d holds electrons the 4s electrons are the outermost, so they are lost first.