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.

701.

Fundamental principle of refrigeration is based on the __________ law of thermodynamics.

A. zeroth
B. first
C. second
D. third
Answer» D. third
702.

Degree of freedom of the system ice-water-vapour will be

A. 0
B. 1
C. 2
D. 3
Answer» B. 1
703.

The standard Gibbs free energy change of a reaction depends on the equilibrium

A. pressure
B. temperature
C. composition
D. all (a), (b) and (c)
Answer» C. composition
704.

Specific __________ does not change during phase change at constant temperature and pressure.

A. entropy
B. Gibbs energy
C. internal energy
D. enthalpy
Answer» C. internal energy
705.

__________ increases with increase in pressure.

A. The melting point of wax
B. The boiling point of a liquid
C. both (a) and (b)
D. neither (a) nor (b)
Answer» D. neither (a) nor (b)
706.

Reduced pressure of a gas is the ratio of its

A. pressure to critical pressure.
B. critical pressure to pressure.
C. pressure to pseudocritical pressure.
D. pseudocritical pressure to pressure.
Answer» B. critical pressure to pressure.
707.

Filling of gas from a high pressure cylinder into small bottles is an example of a/an __________ process.

A. equilibrium
B. adiabatic
C. steady
D. unsteady
Answer» E.
708.

Gibbs free energy at constant pressure and temperature under equilibrium conditions is

A. ‚àû
B. 0
C. maximum
D. minimum
Answer» E.
709.

Entropy of the system decreases, when

A. snow melts into water.
B. a gas expands spontaneously from high pressure to low pressure.
C. water is converted into ice.
D. both (b) & (c).
Answer» E.
710.

Which of the following has the minimum value of COP for a given refrigeration effect?

A. Reverse Carnot cycle.
B. Ordinary vapour-compression cycle.
C. Vapour-compression process with a reversible expansion engine.
D. Air refrigeration cycle.
Answer» E.
711.

Near their critical temperatures, all gases occupy volumes __________ that of the ideal gas.

A. less than
B. same as
C. more than
D. half
Answer» B. same as
712.

In jet refrigerators, the refrigerating fluid is practically always

A. water
B. ammonia
C. freon
D. brine
Answer» B. ammonia
713.

Fugacity is most helpful in

A. representing actual behaviour of real gases.
B. representing actual behaviour of ideal gases.
C. the study of chemical equilibria involving gases at atmospheric pressure.
D. none of these
Answer» B. representing actual behaviour of ideal gases.
714.

The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for$

A. expansion of a real gas.
B. reversible isothermal volume change.
C. heating of an ideal gas.
D. cooling of a real gas.
Answer» C. heating of an ideal gas.
715.

Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57°C and 5.2 atm).$

A. Pressure must be kept below 5.2 atm.
B. Temperature must be kept above - 57°C.
C. Pressure must be kept below 5.2 atm. and temperature must be kept above 57°C.
D. Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively.
Answer» E.
716.

Entropy is a measure of the __________ of a system.

A. disorder
B. orderly behaviour
C. temperature changes only
D. none of these
Answer» B. orderly behaviour
717.

A cylinder contains 640 gm of liquid oxygen. The volume occupied (in litres) by the oxygen, when it is released and brought to standard conditions (0°C, 760 mm Hg) will be __________ litres.$

A. 448
B. 224
C. 22.4
D. data insufficient; can't be computed
Answer» B. 224
718.

The number of degrees of freedom at the triple point of water is

A. 0
B. 1
C. 2
D. 3
Answer» B. 1
719.

No work is done by the system, when a reaction occurs at constant

A. volume
B. temperature
C. pressure
D. none of these
Answer» B. temperature
720.

When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is

A. same in both the phases.
B. zero in both the phases.
C. more in vapour phase.
D. more in liquid phase.
Answer» B. zero in both the phases.
721.

Equilibrium constant of a reaction varies with the

A. initial concentration of the reactant.
B. pressure.
C. temperature.
D. none of these.
Answer» D. none of these.
722.

The reaction A (l) R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The number of degrees of freedom are

A. 1
B. 2
C. 3
D. 0
Answer» C. 3
723.

Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg . K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is$

A. superheated vapour.
B. partially condensed vapour with quality of 0.9.
C. saturated vapour.
D. partially condensed vapour with quality of 0.1.
Answer» B. partially condensed vapour with quality of 0.9.
724.

The equation, PV = nRT, is best obeyed by gases at

A. low pressure & high temperature.
B. high pressure & low temperature.
C. low pressure & low temperature.
D. none of these.
Answer» B. high pressure & low temperature.
725.

As the temperature is lowered towards the absolute zero, the value of, then approaches

A. unity
B. zero
C. that of the heat of reaction
D. infinity
Answer» C. that of the heat of reaction
726.

Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is

A. 300(32/7)
B. 300(33/5)
C. 300(333/7)
D. 300(35/7)
Answer» B. 300(33/5)
727.

Work done in an adiabatic process between two states depends on the

A. rate of heat transmission
B. initial state only
C. end states only
D. none of these
Answer» D. none of these
728.

Which of the following is a thermodynamic property of a system ?

A. Concentration
B. Mass
C. Temperature
D. Entropy
Answer» E.
729.

The theoretical minimum work required to separate one mole of a liquid mixture at 1 atm, containing 50 mole % each of n- heptane and n- octane into pure compounds each at 1 atm is

A. -2 RT ln 0.5
B. -RT ln 0.5
C. 0.5 RT
D. 2 RT
Answer» C. 0.5 RT
730.

The Joule-Thomson co-efficient is defined as (∂T/∂P)H. Its value at the inversion point is$

A. ‚àû
B. 1
C. 0
D. #NAME?
Answer» D. #NAME?
731.

Henry's law is closely obeyed by a gas, when its __________ is extremely high.

A. pressure
B. solubility
C. temperature
D. none of these
Answer» E.
732.

is the mathematical expression

A. Joule-Thomson co-efficient.
B. specific heat at constant pressure (Cp).
C. co-efficient of thermal expansion.
D. specific heat at constant volume (CV).
Answer» D. specific heat at constant volume (CV).
733.

__________ decreases during adiabatic throttling of a perfect gas.

A. Entropy
B. Temperature
C. Enthalpy
D. Pressure
Answer» E.
734.

Compressibility factor for almost all the gases are approximately same at the same

A. pressure and temperature.
B. reduced pressure and reduced temperature.
C. critical pressure and critical temperature.
D. none of these.
Answer» C. critical pressure and critical temperature.
735.

A system undergoes a change from a given initial state to a given final state either by an irreversible process or by a reversible process, then(where, Δ S1 and Δ SR are the entropy changes of the system for the irreversible and reversible processes respectively)

A. Δ S1 is always < Δ SR
B. Δ S1 is sometimes > Δ SR
C. Δ S1 is always > Δ SR
D. Δ S1 is always = Δ SR
Answer» D. Œî S1 is always = Œî SR
736.

The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is

A. 0
B. ‚àû
C. #NAME?
D. #NAME?
Answer» D. #NAME?
737.

In the reaction, C + O2 CO2 ; ΔH = - 94 kcal. What is the heat content (enthalpy)of O2?

A. -94 kcal
B. > -94 kcal
C. < - 94 kcal
D. zero
Answer» E.
738.

Which of the following is not a reversible process ?

A. Expansion of an ideal gas against constant pressure.
B. Atmospheric pressure vaporisation of water at 100°C.
C. Solution of NaCl in water at 50°C.
D. None of these.
Answer» D. None of these.
739.

Refrigeration capacity of a household refrigerator may be round about __________ tons.

A. 0.15
B. 1.5
C. 4.5
D. 6.5
Answer» B. 1.5
740.

Specific volume of an ideal gas is

A. equal to its density.
B. the reciprocal of its density.
C. proportional to pressure.
D. none of these.
Answer» C. proportional to pressure.
741.

A chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is

A. zero
B. positive
C. negative
D. none of these
Answer» D. none of these
742.

The equation Tds = dE - PdV applies to

A. single phase fluid of varying composition.
B. single phase fluid of constant composition.
C. open as well as closed systems.
D. both (b) and (c)
Answer» E.
743.

Which of the following is true for Virial equation of state ?

A. Virial co-efficients are universal constants.
B. Virial co-efficients 'B' represents three body interactions.
C. Virial co-efficients are function of temperature only.
D. For some gases, Virial equations and ideal gas equations are the same.
Answer» D. For some gases, Virial equations and ideal gas equations are the same.
744.

When dilute aqueous solutions of two salts are mixed, the process is associated with

A. decrease in temperature.
B. increase in temperature.
C. no change in temperature.
D. change in temperature which is a function of composition.
Answer» C. no change in temperature.
745.

Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system ?

A. Expansion valve
B. Condenser
C. Refrigerator
D. Compressor
Answer» E.
746.

Absolute zero temperature signifies the

A. minimum temperature attainable.
B. temperature of the heat reservoir to which a Carnot engine rejects all the heat that is taken in.
C. temperature of the heat reservoir to which a Carnot engine rejects no heat.
D. none of these.
Answer» D. none of these.
747.

Degress of freedom at triple point will be

A. 0
B. 1
C. 2
D. 3
Answer» B. 1
748.

"Dry ice" is

A. moisture free ice
B. solid helium
C. solid carbon dioxide
D. none of these
Answer» D. none of these
749.

Variation of equilibrium pressure with temperature for any two phases of a given substances is given by the __________ equation.

A. Gibbs-Duhem
B. Maxwell's
C. Clayperon
D. none of these
Answer» D. none of these
750.

Out of the following refrigration cycles, which one has the minimum COP (Co-efficient of performance)?

A. Air cycle
B. Carnot cycle
C. Ordinary vapour compression cycle
D. Vapour compression with a reversible expansion engine
Answer» B. Carnot cycle