Gases cannot be liquefied above a certain temperature called _________.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe the maximum temperature above which a gas cannot be liquefied, regardless of the pressure applied.

2. **Identifying the Term**: The specific term that describes this temperature is known as the "critical temperature."

3. **Definition of Critical Temperature**: Critical temperature is defined as the temperature above which a substance's vapor cannot be condensed into a liquid, no matter how much pressure is applied.

4. **Conclusion**: Therefore, the answer to the question is "critical temperature."

**Final Answer**: Gases cannot be liquefied above a certain temperature called **critical temperature**.

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