Question

\(0.5-16 \mathrm{m}\) of a saturated vapor is converted to saturated liquid by being cooled in a weighted piston-cylinder device maintained at 50 psia. During the phase conversion, the system volume decreases by \(1.5 \mathrm{ft}^{3} ; 250\) Btu of heat are removed; and the temperature remains fixed at \(15^{\circ} \mathrm{F}\). Estimate the boiling point temperature of this substance when its pressure is 60 psia.

Short answer

Answer: The boiling point temperature of the substance when its pressure is 60 psia is (find the corresponding saturation temperature)°F.

Step-by-step solution

List down the given information

- Initial state: Saturated vapor at 0.5 - 16 m - Cooling process (constant pressure of 50 psia) - Final state: Saturated liquid - Volume change: Decrease by 1.5 ft³ - Heat removed: 250 Btu - Constant temperature: 15°F

Find the saturation temperature at the given pressure

Using the properties table for the substance (Steam or Refrigerant), find the saturation temperature corresponding to the given pressure of 50 psia.

Determine if the temperature remains constant during the phase conversion

Since the problem states that the temperature remains constant at 15°F during the phase conversion, we can infer that the given saturation temperature (from Step 2) must also be 15°F at 50 psia.

Use the saturation pressure-temperature relationship to estimate the boiling point temperature at 60 psia

Now that we know the substance's saturation temperature at 50 psia is 15°F, we can use the saturation pressure-temperature relationship to estimate the boiling point temperature at 60 psia. For this step, we need to consult the same properties table that we used in Step 2. Look for the saturation temperature corresponding to a pressure of 60 psia in the table and note it down as the boiling point temperature at that pressure.

Present the final answer

The boiling point temperature of the substance when its pressure is 60 psia is (find the corresponding saturation temperature)°F.