If the lanthanoid element with x f electrons has a pink color, then the lanthanoid with `(14 - x)` f electrons will have the colour as:

Options

A. Blue
B. reducing agent, reducing agent
C. Green
D. Pink

Explanation

To solve the problem, we need to analyze the relationship between the number of f electrons in lanthanoid elements and their colors. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding the Lanthanoid Series**:
- The lanthanoid series consists of 15 elements, from Lanthanum (La) to Lutetium (Lu), with atomic numbers 57 to 71.
- These elements have partially filled f orbitals, which contribute to their unique colors.

2. **Identifying the Given Information**:
- We are given that a lanthanoid element with `x` f electrons exhibits a pink color.
- We need to determine the color of the lanthanoid element with `(14 - x)` f electrons.

3. **Analyzing the Number of Unpaired Electrons**:
- The color of lanthanoid elements is often related to the number of unpaired electrons in their f orbitals.
- If the element with `x` f electrons has a certain number of unpaired electrons, the element with `(14 - x)` f electrons will have a similar configuration.

4. **Using the Concept of Electron Configuration**:
- In the f-block elements, the maximum number of f electrons is 14 (as there are 7 f orbitals, each can hold 2 electrons).
- The number of unpaired electrons can determine the color. If both configurations (with `x` and `14 - x` f electrons) have the same number of unpaired electrons, they will exhibit similar colors.

5. **Conclusion**:
- Since the element with `x` f electrons is pink, and the element with `(14 - x)` f electrons has the same number of unpaired electrons, it will also be pink.
- Therefore, the lanthanoid with `(14 - x)` f electrons will also have a pink color.

### Final Answer:
The lanthanoid with `(14 - x)` f electrons will have the color **pink**.

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