Thermodynamics

Question 1

Adiabatic process

Answer 1

no energy crosses system boundary

Question 2

Isentropic process

Answer 2

reversible Adiabatic process. No entropy production.

Question 3

throttling process

Answer 3

adiabatic process with pressure drop and constant enthalpy

Question 4

Isobaric process

Answer 4

constant pressure process

Question 5

isochoric or isometric

Answer 5

constant vol process

Question 6

quasiequilibrium or quasistatic process

Answer 6

process that can be divided into discrete equilibrium states

Question 7

work done by the system on the surroundings

Answer 7

+ve work

Question 8

Work done by the environment on the system

Answer 8

-ve work

Question 9

Heat sign conventions

Answer 9

Heat added to system +ve

Heat lost to surroundings -ve

Question 10

Reversible boundary work for a closed system

Answer 10

area under P-V curve, integral of P.dV

Question 11

-ve boundary work

Answer 11

indicates decrease in volume

Question 12

const volume process, close thermodynamic system

Answer 12

Guy-Lussac’s law

Question 13

Open thermodynamic system

Answer 13

working fluid crosses system boundary

Question 14

___________\ can be used to estimate vapor pressures for pure solids and liquids

Answer 14

Clausius clapeyron equation

Question 15

Dry bulb temp

Answer 15

Temp measured by thermometer exposed to air

Question 16

Wet bulb temp

Answer 16

temp of air that has gone through adiabatic saturation. measured by thermometer covered with water-saturated cotton wick

Question 17

Dew-point temp

Answer 17

when moist air is cooled at const pressure process, water condenses at this temp

Question 18

unsaturated air

Answer 18

mixture of water vapor and superheated steam. Dew point temp < Wet bulb temp

Question 19

Kelvin-planck statement of 2nd law

Answer 19

no heat engine can operate in a cycle transferring heat with a single reservoir.

Question 20

Corollary to kelvin planck 2nd law of TD

Answer 20

no heat engine can operate with higher eff than a Carnot engine

Question 21

Clausius statement of 2nd law of TD

Answer 21

no refrigeration or heat pump can operate without a net work input

Question 22

Corollary to Clausius statement

Answer 22

no refrigeration or heat pump operate with higher COP than a Carnot heat pump or refrig

Question 23

Specific properties (u,v,h,s..) are ____ weighted

Answer 23

gravimetrically (Mass or weight)

Question 24

Molar properites are ____ weighted

Answer 24

volumetrically

Question 25

Gibbs free energy

Answer 25

Energy required for a reaction to occur.

-ve value indicates spontaneous reaction

Question 26

Change in gibbs energy

Answer 26

can be used to find exergy without KE and PE terms

Max useful work from an open system at const pr and temp

Question 27

Helmholtz Free Energy

Answer 27

Max work obtainable from a closed system at const vol and temp