Which of the following does not apply to bonding in metals ?

Options

A. Non - directional bonds
B. Mobility of valence electrons
C. Delocalisation of electrons
D. Highly directed bonds

Answer

To solve the question "Which of the following does not apply to bonding in metals?", we need to analyze the characteristics of metallic bonding.

### Step-by-Step Solution:

1. **Understanding Metallic Bonding**:
- Metallic bonding occurs between metal ions and a sea of delocalized (free) electrons. This means that the electrons are not bound to any specific atom and can move freely throughout the metal structure.

**Hint**: Remember that metallic bonding involves a "sea of electrons" that are free to move.

2. **Characteristics of Metallic Bonds**:
- **Non-directional Nature**: The electrostatic attraction between the positively charged metal ions and the negatively charged electrons is non-directional. This means that the forces of attraction do not favor any specific direction, unlike covalent bonds which are directional.

**Hint**: Think about how the forces in metallic bonds act equally in all directions.

3. **Shape and Structure**:
- Because of the non-directional nature of metallic bonding, metals do not form fixed shapes like covalent compounds (which can have specific geometries such as tetrahedral or linear). Instead, metals can be deformed without breaking, which is why they are malleable and ductile.

**Hint**: Consider how metals can be shaped without breaking compared to covalent compounds.

4. **Identifying the Incorrect Statement**:
- If one of the options states that metallic bonds are highly directed or have a specific shape, that statement would not apply to metallic bonding. This is because metallic bonds are characterized by their non-directional nature.

**Hint**: Look for statements that suggest a specific directionality or fixed shape in metallic bonding.

5. **Conclusion**:
- The statement that does not apply to bonding in metals is the one that suggests a highly directed bond or a specific shape, as metallic bonding is inherently non-directional.

### Final Answer:
The characteristic that does not apply to bonding in metals is the "highly directed bond."