Electronic configuration of Zn,Cd and Hg is

Options

A. `(n-1)d^10ns^2`
B. `(n-1)d^9ns^2`
C. `(n-1)d^8ns^2`
D. `(n-1)^8ns^2np^1`

Answer

To find the electronic configurations of zinc (Zn), cadmium (Cd), and mercury (Hg), we need to understand their positions in the periodic table and how electrons fill the orbitals.

### Step-by-Step Solution:

1. **Identify the Elements**:
- Zinc (Zn) has an atomic number of 30.
- Cadmium (Cd) has an atomic number of 48.
- Mercury (Hg) has an atomic number of 80.

2. **Determine the Electron Configuration**:
- The general electronic configuration for transition metals in the d-block is given by the formula:
\[ \text{(N-1)d}^{10} \text{Ns}^2 \]
- Here, N represents the principal quantum number of the outermost shell.

3. **Electronic Configuration of Zinc (Zn)**:
- Zinc is in the 4th period.
- Therefore, its configuration is:
\[ \text{Zn: } [\text{Ar}] 3d^{10} 4s^2 \]
- This means that zinc has 10 electrons in the 3d subshell and 2 electrons in the 4s subshell.

4. **Electronic Configuration of Cadmium (Cd)**:
- Cadmium is in the 5th period.
- Its configuration is:
\[ \text{Cd: } [\text{Kr}] 4d^{10} 5s^2 \]
- This indicates that cadmium has 10 electrons in the 4d subshell and 2 electrons in the 5s subshell.

5. **Electronic Configuration of Mercury (Hg)**:
- Mercury is in the 6th period.
- Its configuration is:
\[ \text{Hg: } [\text{Xe}] 4f^{14} 5d^{10} 6s^2 \]
- This shows that mercury has 14 electrons in the 4f subshell, 10 electrons in the 5d subshell, and 2 electrons in the 6s subshell.

### Final Electronic Configurations:
- **Zinc (Zn)**: \[ [\text{Ar}] 3d^{10} 4s^2 \]
- **Cadmium (Cd)**: \[ [\text{Kr}] 4d^{10} 5s^2 \]
- **Mercury (Hg)**: \[ [\text{Xe}] 4f^{14} 5d^{10} 6s^2 \]