Which of the following is not the characteristic feature of metals?

Options

A. Close-peacket structure
B. Low corrdination number
C. Metallic bonding
D. Give alloys with metals

Explanation

To determine which of the following is not a characteristic feature of metals, we need to analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Characteristics of Metals**:
Metals are known for certain properties, including:
- High electrical and thermal conductivity
- Malleability and ductility
- High density and melting points
- Formation of alloys
- Typically, metals exhibit metallic bonding and a close-packed structure.

2. **Analyzing the Options**:
- **Option 1: Close-packed structure**: Metals often exhibit close-packed structures such as Body-Centered Cubic (BCC) or Face-Centered Cubic (FCC). This is a characteristic feature of metals.
- **Option 2: Low coordination number**: Metals typically have high coordination numbers (like 4, 6, or 8) due to their ability to bond with multiple neighboring atoms. Therefore, a low coordination number is not a characteristic feature of metals.
- **Option 3: Metallic bonding**: This is a defining characteristic of metals. They are held together by metallic bonds, which involve the sharing of free electrons.
- **Option 4: Form alloys with metals**: Metals can combine with other metals to form alloys, which is indeed a characteristic feature of metals.

3. **Conclusion**:
After analyzing all the options, we find that **Option 2: Low coordination number** is not a characteristic feature of metals. Metals are characterized by high coordination numbers.

### Final Answer:
The option that is not a characteristic feature of metals is **Low coordination number**.