A liquid which is permanently supercooled is frequently called a ……….. .

Answer

To solve the question "A liquid which is permanently supercooled is frequently called a ………..", we need to understand the concept of supercooling and the properties of certain liquids.

### Step-by-Step Solution:

1. **Understanding Supercooling**:
- Supercooling occurs when a liquid is cooled below its freezing point without it becoming solid. This state can be maintained under certain conditions.

2. **Characteristics of Supercooled Liquids**:
- A supercooled liquid does not crystallize or change its state even when the temperature is lowered further. It remains in a liquid state despite being below its normal freezing point.

3. **Permanent Supercooling**:
- Some liquids can be supercooled indefinitely without crystallizing. This means they can exist in a liquid state at temperatures where they would typically be solid.

4. **Identifying the Liquid**:
- The most common example of a permanently supercooled liquid is glass. Glass is often described as an amorphous solid or supercooled liquid because it does not have a definite crystalline structure and does not change its properties when cooled further.

5. **Conclusion**:
- Therefore, a liquid which is permanently supercooled is frequently called a **glass**.

### Final Answer:
A liquid which is permanently supercooled is frequently called a **glass**.

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