4.Question 4What is the change in specific enthalpy if water vapor at 80 bar and a quality of 0 is expanded to a saturated vapor at 100 bar? 1 point1317 kJ/kg-1409 kJ/kg1409 kJ/kg2726 kJ/kg

To answer this question, we need to understand the concept of specific enthalpy and how it changes with pressure and quality of a substance.

Specific enthalpy (h) is a property of a substance, defined as the total energy of a system per unit mass. It includes the internal energy of the substance, as well as the work done by the system due to pressure and volume changes.

In this case, we are dealing with water vapor, and we are given that it is at 80 bar pressure with a quality of 0 (meaning it is saturated liquid) and is expanded to a saturated vapor at 100 bar.

The specific enthalpy of water vapor depends on its pressure and temperature. However, the question does not provide the temperature, so we cannot calculate the specific enthalpy directly.

Instead, we can look up the specific enthalpy values for water at the given pressures and quality in a steam table. A steam table lists the thermodynamic properties of water under various conditions.

Unfortunately, without the steam table or the temperature, we cannot provide a numerical answer to this question.

Please refer to a steam table to find the specific enthalpy (h) of water at 80 bar and 100 bar with the given qualities, and calculate the change in specific enthalpy (Δh) as h(100 bar) - h(80 bar).

Remember that the specific enthalpy will decrease when water is compressed (pressure increases) and increase when water is expanded (pressure decreases). So, if the specific enthalpy at 100 bar is less than at 80 bar, the change in specific enthalpy will be negative.

Please note that the actual values may vary depending on the specific steam table used.