Explore topic-wise MCQs in Chemical Engineering.

This section includes 838 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

651.

PVy = constant, holds good for an isentropic process, which is

A. reversible and isothermal.
B. isothermal and irreversible.
C. reversible and adiabatic.
D. adiabatic and irreversible.
Answer» D. adiabatic and irreversible.
652.

An ideal gas is taken around the cycle ABCA as shown in P-V diagram below :The work done by the gas during the cycle is equal to

A. 12 P1V1
B. 6 P1 V1
C. 3 P1V1
D. P1 V1
Answer» D. P1 V1
653.

In case of a close thermodynamic system, there is __________ across the boundaries.

A. no heat and mass transfer
B. no mass transfer but heat transfer
C. mass and energy transfer
D. none of these
Answer» C. mass and energy transfer
654.

For multicomponent multiple phases to be in equilibrium at the same pressure and temperature, the __________ of each component must be same in all phases.

A. chemical potential
B. fugacity
C. both (a) and (b)
D. neither (a) nor (b)
Answer» D. neither (a) nor (b)
655.

In a turbine, the fluid expands almost

A. isothermally
B. isobarically
C. adiabatically
D. none of these
Answer» D. none of these
656.

The internal energy of an ideal gas does not change in a reversible __________ process.

A. isothermal
B. adiabatic
C. isobaric
D. isometric
Answer» B. adiabatic
657.

Enthalpy of a gas depends upon its

A. temperature
B. mass
C. volume
D. pressure
Answer» B. mass
658.

For an incompressible fluid, the __________ is a function of both pressure as well as temperature.

A. internal energy
B. enthalpy
C. entropy
D. all (a), (b) & (c)
Answer» C. entropy
659.

Mollier chart is a __________ plot.

A. pressure vs enthalpy
B. pressure vs volume
C. enthalpy vs entropy
D. temperature vs entropy
Answer» D. temperature vs entropy
660.

Cp of a gas at its critical temperature and pressure

A. becomes zero.
B. becomes infinity.
C. equals 1 kcal/kmol °K.
D. equals 0.24 kcal/kmol °K.
Answer» C. equals 1 kcal/kmol ¬∞K.
661.

The internal energy of an incompressible fluid depends upon its

A. pressure
B. temperature
C. both (a) & (b)
D. neither (a) nor (b)
Answer» C. both (a) & (b)
662.

The third law of thermodynamics states that the

A. heat capacity of a crystalline solid is zero at absolute zero temperature.
B. heat transfer from low temperature to high temperature source is not possible without external work.
C. gases having same reduced properties behave similarly.
D. none of these.
Answer» B. heat transfer from low temperature to high temperature source is not possible without external work.
663.

The temperature at which both liquid and gas phases are identical, is called the __________ point.

A. critical
B. triple
C. freezing
D. boiling
Answer» B. triple
664.

At the critical point of a substance

A. the surface tension vanishes.
B. liquid and vapour have the same density.
C. there is no distinction between liquid and vapour phases.
D. all (a), (b) and (c).
Answer» E.
665.

"Law of corresponding states" says that

A. , two different gases behave similarly, if their reduced properties (i.e. P, V and T) are same.
B. the surface of separation (i. e. the meniscus) between liquid and vapour phase disappears at the critical temperature.
C. no gas can be liquified above the critical temperature, howsoever high the pressure may be.
D. the molar heat of energy of gas at constant volume should be nearly constant (about 3 calories).
Answer» B. the surface of separation (i. e. the meniscus) between liquid and vapour phase disappears at the critical temperature.
666.

Water on heating from 1 to 4°C$

A. contracts
B. expands
C. has same volume
D. may contract or expand
Answer» B. expands
667.

Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.).

A. entropy
B. internal energy
C. enthalpy
D. Gibbs free energy
Answer» E.
668.

Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of

A. fusion
B. vaporisation
C. transition
D. none of these
Answer» D. none of these
669.

The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

A. less than
B. more than
C. same as
D. not related to
Answer» D. not related to
670.

Extensive properties of a thermodynamic system depend upon the __________ of the system.

A. specific volume
B. temperature
C. mass
D. pressure
Answer» D. pressure
671.

In any spontaneous process,

A. only F decreases
B. only A decreases
C. both F and A decreases
D. both F and A increase
Answer» D. both F and A increase
672.

The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called the __________ temperature.

A. critical
B. Boyle
C. inversion
D. reduced
Answer» C. inversion
673.

The main feature of Carnot refrigeration cycle is that, it

A. does not need the addition of external work for its functioning.
B. transfers heat from high temperature to low temperature.
C. accomplishes the reverse effect of the heat engine.
D. none of these.
Answer» D. none of these.
674.

Efficiency of a heat engine working on Carnot cycle between two temperature levels depends upon the

A. two temperatures only.
B. pressure of working fluid.
C. mass of the working fluid.
D. mass and pressure both of the working fluid.
Answer» B. pressure of working fluid.
675.

Degree of freedom of a system consisting of a gaseous mixture of H2 and NH3 will be

A. 0
B. 1
C. 2
D. 3
Answer» E.
676.

For an isothermal reversible compression of an ideal gas

A. only ΔE = 0
B. only ΔH =0
C. ΔE = ΔH = 0
D. dQ = dE
Answer» D. dQ = dE
677.

If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the

A. Maxwell's equation
B. Clayperon-Claussius equation
C. Van Laar equation
D. Nernst Heat Theorem
Answer» C. Van Laar equation
678.

Joule-Thomson experiment is

A. isobaric
B. adiabatic
C. isenthalpic
D. both(b) & (c)
Answer» E.
679.

In an adiabatic process, the

A. heat transfer is zero.
B. temperature change is zero.
C. work done is a path function.
D. enthalpy remains constant.
Answer» B. temperature change is zero.
680.

Activity co-efficient is a measure of the

A. departure from ideal solution behaviour.
B. departure of gas phase from idea] gas law.
C. vapour pressure of liquid.
D. none of these.
Answer» B. departure of gas phase from idea] gas law.
681.

For a spontaneous process, free energy

A. is zero
B. increases
C. decreases whereas the entropy increases
D. and entropy both decrease
Answer» D. and entropy both decrease
682.

The accentric factor of a materical, 'ω', is defined as ω = -log10(Prsat)Tr-1 = 0.7, where, Prsat = reduced vapor pressure, Tr = reduced temperature. The value of accentric factor is always$

A. > 2
B. < 1
C. > 1
D. < 3
Answer» C. > 1
683.

While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is

A. infinity
B. unity
C. constant
D. negative
Answer» D. negative
684.

Gibbs-Duhem equation

A. states that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure.
B. applies only to binary systems.
C. finds no application in gas-liquid equilibria involved in distillation.
D. none of these
Answer» B. applies only to binary systems.
685.

The second law of thermodynamics states that

A. the energy change of a system undergoing any reversible process is zero.
B. it is not possible to transfer heat from a lower temperature to a higher temperature.
C. the total energy of system and surrounding remains the same.
D. none of the above.
Answer» E.
686.

What is the value of ln y (where y = activity co-efficient) for ideal gases ?

A. Zero
B. Unity
C. Infinity
D. Negative
Answer» B. Unity
687.

1st law of thermodynamics is nothing but the law of conservation of

A. momentum
B. mass
C. energy
D. none of these
Answer» D. none of these
688.

The equation, Cp - Cv = R, is true for __________ gas.

A. no
B. any real
C. only ideal
D. both (b) and (c)
Answer» D. both (b) and (c)
689.

Heat of reaction at constant volume is identified with __________ change.

A. enthalpy
B. internal energy
C. either (a) or (b)
D. neither (a) nor (b)
Answer» C. either (a) or (b)
690.

Isobaric process means a constant process.

A. temperature
B. pressure
C. volume
D. entropy
Answer» C. volume
691.

Generation of heat by friction is an example of a/an __________ change.

A. isothermal
B. irreversible
C. adiabatic
D. reversible
Answer» C. adiabatic
692.

Internal energy of an element at 1 atm and 25° C is __________ kcal/kg.mole.$

A. 0
B. 273
C. 25
D. none of these
Answer» B. 273
693.

If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than ΔH for the reaction CH4(g) + C2H4(g) C3H8(g) will be __________ Kcal.$

A. -19.4
B. -30.2
C. 55.2
D. -55.2
Answer» B. -30.2
694.

4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is

A. 4 J
B. ‚àû
C. 0
D. 8 J
Answer» D. 8 J
695.

1m3 of an ideal gas at 500 K and 1000 kPa expands reversibly to 5 times its initial volume in an insulated container. If the specific heat capacity (at constant pressure) of the gas is 21 J/mole . K, the final temperature will be

A. 35 K
B. 174 K
C. 274 K
D. 154 K
Answer» D. 154 K
696.

Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in

A. increased COP.
B. same COP.
C. decreased COP.
D. increased or decreased COP ; depending upon the type of refrigerant.
Answer» B. same COP.
697.

A large iceberg melts at the base, but not at the top, because of the reason that

A. ice at the base contains impurities which lowers its melting point.
B. due to the high pressure at the base, its melting point reduces.
C. the iceberg remains in a warmer condition at the base.
D. all (a), (b) and (c).
Answer» C. the iceberg remains in a warmer condition at the base.
698.

Gibbs free energy of a pure fluid approaches __________ as the pressure tends to zero at constant temperature.

A. infinity
B. minus infinity
C. zero
D. none of these
Answer» C. zero
699.

Critical compressibility factor for all substances

A. are more or less constant (vary from 0.2 to 0.3).
B. vary as square of the absolute temperature.
C. vary as square of the absolute pressure.
D. none of these.
Answer» B. vary as square of the absolute temperature.
700.

For a reversible process involving only pressure-volume work

A. (dF)T, p < 0
B. (dF)T, p > 0
C. (dF)T, p = 0
D. (dA)T, v < 0
Answer» D. (dA)T, v < 0