Which of these is the correct end electronic configuration of curium (atomic number 96) ?

Options

A. `[Rn] 5f^(7)6d^(1)7s^(2)`
B. `[Rn]5f^(7) 6d^(0) 7s^(2)_`
C. `[Rn] 5f^(6) 6d^(0) 7s^(2)`
D. `[Rn] 5f^(10) 6d^(0) 7s^(2)`

Answer

To determine the correct end electronic configuration of curium (atomic number 96), we need to follow the principles of electron configuration.

### Step-by-Step Solution:

1. **Identify the Atomic Number**:
Curium has an atomic number of 96, which means it has 96 electrons.

2. **Follow the Aufbau Principle**:
We will fill the electron orbitals in order of increasing energy levels according to the Aufbau principle.

3. **Fill the Orbitals**:
- Start with the 1s orbital: 1s² (2 electrons)
- Next, fill the 2s orbital: 2s² (2 electrons)
- Fill the 2p orbital: 2p⁶ (6 electrons)
- Fill the 3s orbital: 3s² (2 electrons)
- Fill the 3p orbital: 3p⁶ (6 electrons)
- Fill the 4s orbital: 4s² (2 electrons)
- Fill the 3d orbital: 3d¹⁰ (10 electrons)
- Fill the 4p orbital: 4p⁶ (6 electrons)
- Fill the 5s orbital: 5s² (2 electrons)
- Fill the 4d orbital: 4d¹⁰ (10 electrons)
- Fill the 5p orbital: 5p⁶ (6 electrons)
- Fill the 6s orbital: 6s² (2 electrons)
- Fill the 4f orbital: 4f¹⁴ (14 electrons)
- Fill the 5d orbital: 5d¹⁰ (10 electrons)
- Fill the 6p orbital: 6p⁶ (6 electrons)
- Fill the 7s orbital: 7s² (2 electrons)

4. **Account for Remaining Electrons**:
After filling up to 7s², we have used 86 electrons (2 + 2 + 6 + 2 + 6 + 2 + 10 + 6 + 2 + 10 + 6 + 2 = 86). We have 10 electrons remaining to account for.

5. **Fill the 5f Orbital**:
The next orbitals to fill will be the 5f orbital. For curium, we fill it with 7 electrons: 5f⁷.

6. **Fill the 6d Orbital**:
The last electron will go into the 6d orbital: 6d¹.

7. **Final Electronic Configuration**:
Thus, the complete electronic configuration for curium (Cm, atomic number 96) is:
\[ \text{[Rn]} 5f^7 6d^1 7s^2 \]

### Conclusion:
The correct end electronic configuration of curium is:
\[ \text{[Rn]} 5f^7 6d^1 7s^2 \]