Thermodynamics final chap 7

What is entropy definition in Statisical Thermo

Degree of diorder of substance

Available microstaes and unterainty of molecular positions

What is the defintion of entropy in classical thermodynamics

mesure of irreversibilites (entropy is nort consever but is a thermdynamic property)

What happens to entropy when Isothermal increase in volume

Temp remain constant but added possible positions (increasing entropy)

What happens to entropy when isometric increase in temprature

volocity distibution range increases giving more possible kinetic energyies(entropy increses)

WHat happens to entropy there is a Isometric/Isothermal increase in amass

More possible positions and distributions of energy (entropy increses)

What happensto the entropy if there is a mixing of multiple substances isothermally

Temp remains constant, but added possible postions and particle types(increase in entropy)

When is the clausis inequality equal ot zero

When the system is totally reversible

When is the clauis inequallity not equal to zero. And what is it equal to

Irreversible cycles;less than zero

When can changes in entropy be calculated?

when the system is internally reversible

What is the special isothermal reversible case

What is the carnot cycle relationship to entropy change. what ist he derivatio

The carnot cycle returns to its origianl state in reversible process; therfore entropy is a state function that returns to the original state.

What is the carnot cycle look like on Pv diagram

What does the carnot cycle look like on the Ts diagram

What is the increase of entropy principle

Some entropy is created during an irreverible process,due to irribvesibliles

What are the rule s of the increase of entropy principle

Process must occur in direction of Sgen > 0

Entropy is not conserved it is allways increases

S gen is a quantiy mesure of the irriversibilty of the system _thus it can be used to msure the prefornce of devices.

What are some caustions about increase in entropy principle

Change in entropy of a closed system can be negative,but s gen of the whole sustem can never be negative.

what is the rest of this derivation for Sgen

What are the assumptions of isentropic processes

It is internally reversible and adiabatic

Which composnets can be modeeled as near adiabatic(isentropic)?

Pumps Nozzles turbines diffusers compressor

When is the area inder t-s diagram the total heat transfer

Only when it is an internally reversible process.

When are the T-ds reations valid

it is valid for all process in closed and open system. Reversible or irreversible Valid only if realtionships are known

What assumptions are made for entropy change of liquids and solids

Negligible change in volume/specific volume

What assumptions are made for entropy changes of ideal gases(constant volume). Which equation will you use?(CONSTANT VOLUME)

What assumptions are made for entropy changes of ideal gases(constant Pressure)? Which equation do you use CONSTANT PRESUURE

What is exact analysis and how is it used to solve changes in entropy of ideal gas

You use the charts to reqfrence the the entropy (A-17 through A-18) and then useing the s dot for the places in the equations

What is average analysis?

You use the average temprature value to determine the cp or cv value

What do the y and x axis repersent on a mollier diagram? what do mollier diagram represent in terms of work and irreversibility?

The veritical distance repersent change in enthalpy. for adiabatic steady flow devices thits is a mesure of work.

The horizontal diance is the change in entropy. For adiabatic flow devices this is a mesure of irreversibilty

What is the third law of thermodynamics nad how does it realate to entropy

Entropy of a pure crystaline subatance at absolute zero temp is zero. THe absolute entropy is deffines from reffecne point zero

this is why all the tables have s dot on them

What does isentropic efficency and what does it repersent in Turbine, compressor, and pump?

Isentropic process the highest performing for steaady flow componets value is less than 1

Turbines outputs the most work

compressors and pumps it puts in the least abount of work

What does hte isentropic ves a real process look like on ts diagram

What do isentropic efficy look like for nozzle and diffuser

It is teh ratio of actual kinstic energy vs isentropic kinetic energy

isentropic nozzle will maximizr kietic energy at the exit state