Write general outer electronic configuration of 4f series elements.

Answer

To find the general outer electronic configuration of the 4f series elements, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Series**: The 4f series elements are part of the f-block of the periodic table. The f-block consists of lanthanides and actinides.

2. **Understand the General Configuration**: The general electronic configuration for f-block elements can be expressed as:
\[ n-2 f^{0-14} \, n-1 d^{0-1} \, ns^{2} \]
Here, \(n\) represents the principal quantum number.

3. **Determine the Value of n**: For the 4f series, we know that \(n-2 = 4\). Therefore, we can find \(n\):
\[ n = 4 + 2 = 6 \]

4. **Substitute n into the General Configuration**: Now that we have \(n = 6\), we can substitute this value into the general configuration:
\[ 4f^{0-14} \, 5d^{0-1} \, 6s^{2} \]

5. **Write the Final Configuration**: Thus, the general outer electronic configuration of the 4f series elements is:
\[ [Xe] \, 4f^{1-14} \, 5d^{0-1} \, 6s^{2} \]
where \([Xe]\) represents the electron configuration of xenon, which is the noble gas preceding the lanthanides.

### Final Answer:
The general outer electronic configuration of the 4f series elements is:
\[ [Xe] \, 4f^{1-14} \, 5d^{0-1} \, 6s^{2} \]

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