Thermo Session 2

1. What is a compressed liquid?

• A liquid that is about to vaporize

• A liquid that has a temperature higher than the saturation temperature at a given pressure

• A liquid that has a temperature lower than the saturation temperature at a given pressure

• A mixture of liquid and vapor in equilibrium

2. Which of the following statements about phase change is correct?

• The temperature always increases during a phase change

• The temperature remains constant during a phase change if pressure is held constant

• The pressure always increases during a phase change

• The pressure remains constant during a phase change regardless of conditions

3. The point where all three phases (solid, liquid, vapor) coexist in equilibrium is called:

• Critical point

• Superheated point

• Saturation point

• Triple point

4. The latent heat of fusion refers to:

• The energy required to change a solid to a liquid at constant temperature and pressure

• The energy required to completely vaporize a liquid

• The energy absorbed during freezing

• The energy required to increase the temperature of a substance by 1°C

5. What happens to specific volume during the vaporization process at constant pressure?

• It decreases

• It remains constant

• It increases significantly

• It fluctuates randomly

6. Which of the following is NOT a property diagram commonly used to study phase changes?

• Temperature-Volume (T-v) diagram

• Enthalpy-Momentum (H-M) diagram

• Pressure-Volume (P-v) diagram

• Pressure-Temperature (P-T) diagram

7. What is the quality (x) of a substance in a saturated liquid state?

• 0

• 0.5

• 1

• Undefined

8. In a phase diagram, what happens above the critical point?

• The substance exists as a mixture of saturated liquid and vapor

• The liquid and vapor phases are indistinguishable

• The substance becomes a superheated vapor

• The pressure of the substance decreases rapidly

9. What does the specific volume (v) of a saturated liquid-vapor mixture depend on?

• The amount of heat transferred

• The mass fraction of vapor in the mixture (quality x)

• The latent heat of fusion

• The superheated vapor pressure

10. If a compressed liquid table is unavailable, how can the enthalpy of a compressed liquid be estimated?

• By using the ideal gas equation

• By interpolating between superheated vapor values

• By assuming the properties of the compressed liquid are the same as the saturated liquid at the same temperature

• By using the latent heat of fusion