chapter 3 and 4

Question 1

Phase

Answer 1

Matter which is homogeneous throughout in both its chemical and physical structure. ex- air = single phase
water with ice = 2 phase

Question 2

Homogeneous

Answer 2

Matter is all the same state, solid, liquid, or gas

Question 3

Pure Substance

Answer 3

A substance that is uniform and invariable in chemical composition. ex- helium, water and ice

Question 4

liquid to gas

Answer 4

Vaporization

Question 5

gas to liquid

Answer 5

Condensation

Question 6

solid to liquid

Answer 6

Melting (fusion)

Question 7

liquid to solid

Answer 7

freezing

Question 8

solid to gas

Answer 8

sublimation

Question 9

gas to solid

Answer 9

deposition

Question 10

Phase Rule

Answer 10

f=c-p+2
f= degrees of freedom
c=number of components
p=number of phases
 at equilibrium for a system of any composition.

Question 11

The ______ state of a closed system at equilibrium is its condition as described by the values of its intensive thermodynamic properties.

Answer 11

intensive

Question 12

For a simple compressible system, specifying any _____ independent intensive thermodynamic properties will fix the other intensive thermodynamics properties of the system.

Answer 12

2

Question 13

Examples of intensive properties

Answer 13

(Doesn’t depend on amount of matter or size)

Pressure, Temperature, Density, Specific Volume, Internal Energy, Enthalpy, Entropy.

Question 14

saturation temperature

Answer 14

temp at which a phase change happens for a specific pressure

Question 15

True or false. Within two-phase regions, pressure and temperature ARE independent.

Answer 15

False

Question 16

Critical point

Answer 16

the point where saturated liquid and saturated vapor lines meet

Question 17

isotherms

Answer 17

line of constant temperature

High left to low right on p-v

Question 18

isobar

Answer 18

line of constant pressure

low left to high right t-v

Question 19

true of false. while in dome if p-v or t-v diagram temp and pressure remain constant from specific volume changes

Answer 19

true

Question 20

compressed liquid

Answer 20

a liquid with a temp lower than saturation temp for

Question 21

quality (x) equation

Answer 21

percent of mixture that is vapor

x=mvapor/(mliquid+mvapor)

Question 22

superheated vapor

Answer 22

when temp is higher than the sat temp for corresponding pressure

Question 23

total volume saturated liquid formula

Answer 23

V=vf+x(vg-vf)

vf=liquid vg=vapor

Question 24

specific enthalpy (h)

Answer 24

h=u+pv

enthalpy= internal energy + work due to expansion

Question 25

linear interpolation

Answer 25

vactual= v@ref1 +[(v@ref2 - v@ref1)/(ref2-ref1)] (actual-ref1)

Question 26

Extensive form of internal energy and enthalpy

Answer 26

U and H (uppercase is important)

Question 27

Intensive form of internal energy and enthalpy

Answer 27

u and h (lowercase is important)

Question 28

Constant volume process equation

Answer 28

u2-u1=cv(T2-T1)

Question 29

Constant pressure process equation

Answer 29

h2-h1=cp(T2-T1)

Question 30

specific heat ratio

Answer 30

k=cp/cv

Question 31

True of False. For a liquid, there is little change in v,u,h,and s at different Temperatures and fixed Pressure.

Answer 31

False | there is little change at different Pressures and fixed temperature.

Question 32

incompressible substance

Answer 32

any substance whose properties do not change with pressure, or have very minor changes.

Question 33

generalized compressibility only applies to _____

Answer 33

gases

Question 34

what does a horizontal line above a variable mean

Answer 34

molar unit. | unit times molar weight (g/mol)

Question 35

what does it mean when z=1

Answer 35

ideal gas P is much less than Pc T is much greater than Tc

Question 36

pressure and temp reduced equations

Answer 36

Pr=P/Pc Pc=critical pressure | Tr=T/Tc Tc=critical temp

Question 37

ideal gas equation (3 forms)

Answer 37

pv=RT (lowercase v is important) pV=mRT m=mass pV=nRT (with line above R) n=number of moles

Question 38

if a gas behaves as an ideal gas, then its specific internal energy and specific enthalpy, depends only on _____

Answer 38

temperature

Question 39

polytropic process formula and process for N=1,0,and k

Answer 39

pv^N=constant or pV^N=constant N=1 - isothermal pv=Constant N=0 isobaric process p=Constant N=k adiabatic process Q=0

Question 40

Mass rate balance

Answer 40

the rate at which mass accumulates in the control volume is the difference between mass flow in and flow out

Question 41

Energy rate balance

Answer 41

the rate at which energy accumulates. the difference between heat flow rate in and power out AND difference between mass carries energy into and out of control volume

Question 42

1st law of thermodynamics for open system

Answer 42

rate of energy accumulation= Qdot - Wdot +mdot-i (ei) - mdot-e (ee)

Question 43

Flow work

Answer 43

work done BY the flow (Wdot)

Question 44

control volume work

Answer 44

work done BY the control volume (Wdot-cv) integral of pdv | ex - work done by turning a shaft or electricity

Question 45

work done ON system by mass entering

Answer 45

negative

Question 46

work done On environment as mass exits

Answer 46

positive

Question 47

steady state Qdot=0 if | *IMPORTANT*

Answer 47

small surface area system is insulated small time interacting with system and environment

Question 48

steady state Wdot=0 if | *IMPORTANT*

Answer 48

no change in system volume (fixed container) | no turbines/pumps or electrical devices

Question 49

steady state gz=0 if | *IMPORTANT*

Answer 49

no significant change in elevation from inlet and outlet

Question 50

vi^2-ve^2=0 if | *IMPORTANT*

Answer 50

inlet and outlet are the same size

Question 51

Nozzle

Answer 51

passage where velocity increases in direction of flow Ve greater than Vi Pe less than Pi Enters wide end exits narrow end

Question 52

diffuser

Answer 52

passage where velocity decreases in direction of flow Ve less than Vi Pe greater than Pi enters narrow end, exits wide end

Question 53

Turbine

Answer 53

a device in which --power is developed-- as a result of a gas or liquid passing through a set of blades attached to a shaft free to rotate.

Question 54

compressors and pumps

Answer 54

devices in which --work is done on the substance-- flowing through them to change the state of the substance, typically to --increase the pressure and/or elevation--

Question 55

difference between compressor and pump

Answer 55

compressor- uses gas | pump - uses liquid

Question 56

Heat exchanger | Direct contact

Answer 56

a mixing chamber in which hot and cold streams are --mixed directly-- ex- water faucet

Question 57

heat exchanger | tube-within-a-tube counterflow

Answer 57

a gas or liquid steam is --separated-- from another gas or liquid by a wall through which energy is conducted. heat transfer occurs from the hot stream to the cold stream as the streams flow in opposite directions. ex- radiator

Question 58

specific heat (c) definition

Answer 58

The heat required to raise the temperature of a unit mass of a substance by a certain amount. (usually 1 degree)