Outer electronic configurayion of f block elements is

Options

A. `(n+1)f^1-14 (n-1)d^(0-1)ns^2`
B. `(n-2)f^(1-14)(n+1)d^(0-1)ns^2`
C. `(n-2)f^(1-14)(n-1)d^(0-1)ns^2`
D. none of the above

Answer

To determine the outer electronic configuration of f-block elements, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the f-block elements**:
- The f-block elements consist of the lanthanides (elements 57-71) and actinides (elements 89-103) in the periodic table.

2. **Understand the electronic configuration**:
- The outer electronic configuration of f-block elements is characterized by the filling of the f-orbitals.

3. **General Configuration**:
- The general outer electronic configuration for f-block elements can be expressed as:
- \( [Xe] 6s^2 4f^{1-14} \) for lanthanides
- \( [Rn] 7s^2 5f^{1-14} \) for actinides
- Here, \( [Xe] \) and \( [Rn] \) represent the electron configurations of the noble gases preceding these elements.

4. **Count the electrons**:
- In the f-block, the f-orbitals can hold a maximum of 14 electrons (from \( f^1 \) to \( f^{14} \)).
- The s-orbital can hold 2 electrons, which is common in both lanthanides and actinides.

5. **Final Configuration**:
- Therefore, the outer electronic configuration of f-block elements can be summarized as:
- \( n-2 f^{1-14} n-1 d^{0-1} n s^2 \)
- Where \( n \) represents the principal quantum number corresponding to the outermost shell.

### Final Answer:
The outer electronic configuration of f-block elements is generally expressed as:
\[ n-2 f^{1-14} n-1 d^{0-1} n s^2 \]

---