Points 15, True/False: If a closed system consisting of a si… If a closed system
ID: 2074714 • Letter: P
Question
Points 15, True/False: If a closed system consisting of a si… If a closed system consisting of a simple compressible substance is at equilibrium, only one phase can be present Answer rue False Points 16, Multiple Choice: A two-phase liquid-vapor mixture has A two-phase liquid-vapor mixture has 0.2 kg of saturated water vapor and 0.6 kg of saturated liquid. The quality is Answer a 25% b. 75% C.60% d 20% Points 17. Multiple Choice: A system consists of a two-phase liqu… Asystem consists of a two-phase liquid-vapor mixture of 5 kg of Refrigerant 134a· one kg is saturated liquid the quality lf percent Answer a. 80 b. 20 c. 16 d. 83Explanation / Answer
15. True
If we consider a gas in a closed system. It can be in equilibrium at some pressure & temperaure but not at all pressure & temperaure. So this statement is conditionally true but it is not true for all cases.So single phase can be present.
16. Quality is ratio of mass of saturated vapour to total saturated including liquid and vapour i.e.
Quality= mass of saturated vapour / total mass of liquid and vapour
given
mass of saturated vapor = 0.2 kg
total mass of saturated liquid = 0.6 kg
total mass of saturated liquid and vapor = ( 0.2 + 0.6) = 0.8
Quality = 0.2/0.8
= 0.25 or 25%
So 25 % vapor present in liquid- vapor mixture.
17. Same theory as written in question 16.
Total mass of saturated liquid and vapor = 5 kg
total mass of saturated liquid = 1 kg
mass of saturated vapor = (5-1) kg
= 4 kg
Quality = 4/5
= 0.8 or 80%
So 25 % vapor present in liquid- vapor mixture.