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[...]... Properties and State of a System The matter in a system may exist in several phases: a solid, a liquid, or a gas A phase is a quantity of matter that has the same chemical composition throughout; that is, it is homogeneous It is all solid, all liquid, or all gas Phase boundaries separate the phases in what, when taken as a whole, is called a mixture Gases can be mixed in any ratio to form a single phase Two... boundary as either heat or work We will present equations that relate the transformations and transfers of energy to properties such as temperature, pressure, and density The properties of materials thus become very important Many equations will be based on experimental observations that have been presented as mathematical statements, or laws: primarily the first and second laws of thermodynamics The mechanical... system are at the same increased temperature If a system would undergo a large change in its properties when subjected to some small disturbance, it is said to be in metastable equilibrium A mixture of gasoline and air, and a bowling ball on top of a pyramid are examples When a system changes from one equilibrium state to another, the path of successive states through which the system passes is called a. .. measured in meters of water or millimeters of mercury In many relations, absolute pressure must be used Absolute pressure is gage pressure plus the local atmospheric pressure: Pabs = Pgage + Patm (1.14) A negative gage pressure is often called a vacuum, and gages capable of reading negative pressures are vacuum gages A gage pressure of −50 kPa would be referred to as a vacuum of 50 kPa (the sign is omitted)... standard conditions It should be noted that atmospheric pressure is highly dependent Pgage Pgage = 0 Pgage (negative pressure, a vacuum) Pabs Patm (measured by a barometer) Pabs Pabs = 0 Figure 1.8 Absolute and gage pressure CHAPTER 1 Basic Principles 13 on elevation; in Denver, Colorado, it is about 84 kPa; in a mountain city with elevation 3000 m, it is only 70 kPa In Table B.1, the variation of atmospheric... CHAPTER 1 Basic Principles 11 1.7 Pressure In gases and liquids, the effect of a normal force acting on an area is the pressure If a force ΔF acts at an angle to an area A (Fig 1.7), only the normal component Δ Fn enters into the definition of pressure: P = lim A 0 Δ Fn A (1.9) The SI unit of pressure is the pascal (Pa), where 1 Pa = 1 N/m2 The pascal is a relatively small unit so pressure is usually... liquids that are miscible form a mixture when mixed; but liquids that are not miscible, such as water and oil, form two phases A pure substance is uniform in chemical composition It may exist in more than one phase, such as ice, liquid water, and vapor, in which each phase would have the same composition A uniform mixture of gases is a pure substance as long as it does not react chemically (as in combustion)... passing from one state to the next, the deviation from equilibrium is small, and thus negligible, a quasiequilibrium process occurs; in this case, each state in the process can be idealized as an equilibrium state Quasiequilibrium processes can approximate many processes, such as the compression and expansion of gases in an internal combustion engine, with acceptable accuracy If a system undergoes a. .. 32) 9 (1.15) ABSOLUTE TEMPERATURE SCALE The second law of thermodynamics will allow us to define an absolute temperature scale; however, since we have not introduced the second law at this point and we have CHAPTER 1 Basic Principles 15 immediate use for absolute temperature, an empirical absolute temperature scale will be presented The relations between absolute and relative temperatures are TK = TC...x CHAPTER 9 Thermodynamics Demystified Combustion 9.1 Combustion Equations 9.2 Enthalpy of Formation, Enthalpy of Combustion, and the First Law 9.3 Adiabatic Flame Temperature Quiz No 1 Quiz No 2 227 227 APPENDIX A Conversion of Units 245 APPENDIX B Material Properties 247 APPENDIX C Steam Tables 253 APPENDIX D R13 4a 263 APPENDIX E Ideal-Gas Tables 269 APPENDIX F Psychrometric Chart 277 APPENDIX . 97 8-0 -0 7-1 6059 9-1 , MHID: 0-0 7-1 6059 9-1 . All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names. Climate Change Demystified Hedge Funds Demystified Investing Demystified Italian Demystified Java Demystified JavaScript Demystified Lean Six Sigma Demystified Linear Algebra Demystified Macroeconomics. and State of a System The matter in a system may exist in several phases: a solid, a liquid, or a gas. A phase is a quantity of matter that has the same chemical composition throughout; that