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Consider the following statements: 1. There is no change in temperature when a liquid is being evaporated into vapour 2. Vapour is a mixed phase of liquid and gas in the zone between saturated liquid line and saturated vapour line 3. The saturated dry vapour curve is steeper as compared to saturated liquid curve on a T-s diagram 4. The enthalpy of vaporization decreases with increase in pressure Which of the above statements are correct?

Consider the following statements: 1. There is no change in temperature when a liquid is being evaporated into vapour 2. Vapour is a mixed phase of liquid and gas in the zone between saturated liquid line and saturated vapour line 3. The saturated dry vapour curve is steeper as compared to saturated liquid curve on a T-s diagram 4. The enthalpy of vaporization decreases with increase in pressure Which of the above statements are correct? Correct Answer 1, 2 and 4 only

A T-s diagram of phase change is shown in the figure,

Observations

  • When the liquid starts evaporating the temperature and pressure both remains constant.
  • Vaporisation is the region between saturated liquid line and the saturated vapour line where the phase of water is changing from liquid to vapour therefore both the liquid and gas co-exists in that region.
  • The saturated liquid curve is more steeper than saturated dry vapour curve
  • The enthalpy of evaporation is the difference between the enthalpies at saturated liquid state and saturated vapour state this difference decrease with the increase in pressure. Enthalpy of vaporisation decreases with increase in pressure.

Related Questions

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