Find the electronic configuration of the element that is placed just below the element with atomic number 25 in the same group. 

Options

A. `1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3ď^5`
B. `1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4ď^5`
C. `1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^6`
D. `1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^1 4d^5`

Answer

To find the electronic configuration of the element that is placed just below the element with atomic number 25 (which is Manganese), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Element with Atomic Number 25**:
- The element with atomic number 25 is Manganese (Mn).

2. **Determine the Element Below Manganese**:
- Manganese is located in Group 7 of the periodic table. The element directly below Manganese in the same group is Technetium (Tc), which has an atomic number of 43.

3. **Find the Atomic Number of Technetium**:
- Technetium has an atomic number of 43.

4. **Write the Electronic Configuration for Technetium**:
- The electronic configuration is determined by filling the atomic orbitals according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle.
- The order of filling is as follows:
- 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, etc.
- For Technetium (43 electrons), the electronic configuration is:
- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d⁵.

5. **Final Electronic Configuration**:
- Therefore, the electronic configuration of Technetium (Tc) is:
- **1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d⁵**.