The liquid phase of a pure substance is termed as \(\underline{\hspace{2cm}}\), if its temperature is lower than the saturation temperature corresponding to its pressure \(P\).
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- super-heated liquid
- sub-cooled liquid
- metastable liquid
- flashing liquid
The Correct Option is B
Solution and Explanation
Step 1: Understand the phases of liquid.
- Super-heated liquid: This is a liquid that has been heated above its saturation temperature at a given pressure.
- Sub-cooled liquid: This is the correct term when the liquid's temperature is lower than its saturation temperature.
- Metastable liquid: This refers to a liquid that is in a non-equilibrium state, often unstable, but not the correct term for sub-cooled liquid.
- Flashing liquid: This refers to a liquid that undergoes a phase change to vapor under reduced pressure.
Step 2: Conclusion.
The liquid phase is termed sub-cooled liquid when its temperature is lower than the saturation temperature at the given pressure.
Final Answer: \text{(B) sub-cooled liquid}
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