To determine the electronic configuration of copper (Cu) with atomic number 29 in its ground state, we need to follow a systematic approach to fill the electrons into the appropriate orbitals.
### Step-by-Step Solution:
1. **Identify the Atomic Number**:
- The atomic number of copper (Cu) is 29, which means it has 29 electrons.
2. **Know the Order of Orbital Filling**:
- According to the Aufbau principle, electrons fill orbitals in order of increasing energy. The order of filling is:
- 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, etc.
3. **Fill the Electrons in the Orbitals**:
- Start filling the electrons according to the order:
- 1s: 2 electrons → 1s²
- 2s: 2 electrons → 2s²
- 2p: 6 electrons → 2p⁶
- 3s: 2 electrons → 3s²
- 3p: 6 electrons → 3p⁶
- 4s: 2 electrons → 4s²
- 3d: 10 electrons → 3d¹⁰
- At this point, we have filled 2 + 2 + 6 + 2 + 6 + 2 + 10 = 30 electrons, but we only need to account for 29 electrons.
4. **Adjust for Copper's Exception**:
- Copper is an exception to the typical filling order. Instead of having 4s² and 3d⁹, one electron from the 4s orbital is promoted to the 3d orbital to achieve a more stable configuration.
- Thus, for copper, we have:
- 4s: 1 electron → 4s¹
- 3d: 10 electrons → 3d¹⁰
- This gives us a total of 29 electrons: 2 (1s) + 2 (2s) + 6 (2p) + 2 (3s) + 6 (3p) + 1 (4s) + 10 (3d) = 29.
5. **Write the Final Electronic Configuration**:
- The final electronic configuration for copper in its ground state is:
- **1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹**
### Conclusion:
The correct electronic configuration of copper (Cu) in its ground state is **1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹**.
