The melting and boiling points of a substance 'X' are `-110^@C` and `-85^@C` respectively. At which of the following range of temperatures will 'X' exist as a liquid?

Options

A. Between `–125^@C` and `-90^@C`
B. Between `-100^@C` and `-95^@C`
C. Between `-100^@C` and `-60^@C`
D. Between `-210^@C` and `-95^@C`

Answer

To determine the temperature range in which substance 'X' exists as a liquid, we need to analyze the given melting and boiling points.

1. **Identify the Melting and Boiling Points**:
- The melting point of substance 'X' is `-110°C`.
- The boiling point of substance 'X' is `-85°C`.

2. **Understanding the States of Matter**:
- A substance is solid below its melting point.
- A substance is liquid between its melting point and boiling point.
- A substance is gas above its boiling point.

3. **Determine the Temperature Range for Liquid State**:
- Since the melting point is `-110°C`, the substance will be solid below this temperature.
- Between `-110°C` and `-85°C`, the substance will exist as a liquid.
- Above `-85°C`, the substance will be in the gaseous state.

4. **Conclusion**:
- Therefore, substance 'X' will exist as a liquid in the temperature range of `-110°C` to `-85°C`.

### Final Answer:
Substance 'X' exists as a liquid in the temperature range of `-110°C` to `-85°C`.

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