华南理工大学《传质与分离(双语)》填空选择模拟题集.docVIP

1.Thecauseofmoleculardiffusionis(concentrationdifference)

2.Thebasicequationfordiffusioninanonturbulentfluidphaseincludestwoterms:

(convectivebulkflow);(moleculardiffusion)

3.Theconcentrationprofileforanequimolalcounterdiffusionisexpressedas:

()

4.Theconcentrationdistributionforaone-waydiffusionisexpressedas

()

5.Thediffusionfluxforanequimolardiffusionis(c)thatforaone-waydiffusion

A)largerthanB)equaltoC)lessthanD)uncertain

6.ThediffusivityofNH3-N2is2.30×10-5m2/sat25℃and101.3kPa,usingChapman-EnskogequationforbinarydiffusiontopredictthediffusivityofNH3-N2systemat50℃and202.6kPa(),anddiffusionfluxwill()withkeepingthedrivingforceofdiffusionunchanged.

7.Whenthegas-liquidequilibriumrelationcanbeexpressedasy=mx,usingtwo-filmtheorytoderivethecorrelationbetweentheoverallmasstransfercoefficient(Kx)basedontheoverallliquiddrivingforceandtheindividualfilmcoefficients(kxandky).

1

Equilibriumrelation

y=mx2

substitutingequation2foryintotheequation1gives

then

8.Twofilmtheoryclaimsthattherewouldbe(A)totransferacrossinterface.

A)noresistanceB)resistanceC)uncertain

1.TheHenry’slawconstantmwill(increase),andthesolubilityofsolublegaswill(decrease)withrisingintemperatureifthetotalpressureofsystemkeepsunchanged.

TheHenry’slawconstantmwill(decrease),andthesolubilityofsolublegaswill(increase)withrisinginpressureifthetemperatureofsystemkeepsunchanged

2.Foranidealsolution,thepartialpressureofcomponentingasis(proportional)tomolefractionofcomponentandtheproportionalityis(vaporpressureofpuresubstance)

3.Theequilibriumrelationwit