A mixture of saturated liquid water and saturated steam at P = 0.3 MPa has a quality q = 0.7. What is the specific enthalpy of this mixture? (Use Appendix A for data.)
A. 2075. N/kg
B. 2075. kJ/kg
C. 2300. kJ/kg
D. 1210. kJ/kg
E. 1948. kJ/kg
A. Incorrect. Watch the units!
B. Correct. Using the definition of quality, the given pressure, the steam tables and Equation 2.11 you calculated the correct value.
C. Incorrect. Review the definition of quality and your algebra.
D. Incorrect. You are probably using the incorrect definition of quality. In this book, quality is the vapor fraction of a mixture.
E. Incorrect. You misread the steam tables. Carefully review them and then redo your calculations.
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Example 18.12
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