Explore topic-wise MCQs in Chemical Engineering.

This section includes 469 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

201.

_ Lenz's law results from the law of conservation of$?

A. Mass
B. Momentum
C. Energy
D. None of these
Answer» D. None of these
202.

_ Specific/molar Gibbs free energy for a pure substance does not change during$?

A. Sublimation
B. Vaporisation
C. Melting
D. Either A, B or C
Answer» E.
203.

_ __________ does not change during phase transformation processes like sublimation, melting & vaporisation.$?

A. Entropy
B. Gibbs free energy
C. Internal energy
D. All of the above
Answer» C. Internal energy
204.

_ The adiabatic throttling process of a perfect gas is one of constant enthalpy$?

A. In which there is a temperature drop
B. Which is exemplified by a non-steady flow expansion
C. Which can be performed in a pipe with a constriction
D. In which there is an increase in temperature
Answer» D. In which there is an increase in temperature
205.

_ The number of degrees of freedom for an azeotropic mixture in a two component vapour-liquid equilibria is/are$?

A. Zero
B. One
C. Two
D. Three
Answer» C. Two
206.

_ An irreversible process$?

A. Is the analog of linear frictionless motion in machines
B. Is an idealised visualisation of behaviour of a system
C. Yields the maximum amount of work
D. Yields an amount of work less than that of a reversible process
Answer» E.
207.

_ The number of degrees of freedom for a mixture of ice and water (liquid) are$?

A. 2
B. 3
C. 1
D. 0
Answer» D. 0
208.

_ 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
209.

_ If atmospheric temperature and dew point are nearly equal, then the relative humidity is$?

A. Zero
B. 50%
C. Almost 100%
D. Unpredictable
Answer» D. Unpredictable
210.

_ Extensive properties of a thermodynamic system depend upon the __________ of the system.$?

A. Specific volume
B. Temperature
C. Mass
D. Pressure
Answer» D. Pressure
211.

_ 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.
212.

_ 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
213.

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

A. Boyle
B. Inversion
C. Critical
D. Reduced
Answer» B. Inversion
214.

_ Entropy change of the reaction, H‚ÇÇO(liquid) H‚ÇÇO(gas), is termed as the enthalpy of$?

A. Solution
B. Vaporisation
C. Formation
D. Formation
Answer» C. Formation
215.

_ At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is$?

A. 1.572
B. 1.9398
C. 3.389
D. 4.238
Answer» B. 1.9398
216.

_ In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process.$?

A. Isothermal
B. Adiabatic
C. Isentropic
D. Polytropic
Answer» D. Polytropic
217.

_ Gibbs-Duhem equation relates composition in liquid phase and the __________ at constant temperature & pressure.$?

A. Fugacity
B. Partial pressure
C. Activity co-efficient
D. A, B, and C
Answer» E.
218.

_ If an ideal solution is formed by mixing two pure liquids in any proportion, then the __________ of mixing is zero.$?

A. Enthalpy
B. Volume
C. Both A & B
D. Neither A nor B
Answer» D. Neither A nor B
219.

_ 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
220.

_ The unity of Planck's constant 'h' in the equation, E = hv is$?

A. J/s
B. J.S
C. J/kmol
D. Kmol/J
Answer» C. J/kmol
221.

_ Which of the following is Virial equation of state?$?

A. (p + a/V²)(V - b) = nRT
B. PV = nRT
C. PV = A + B/V + C/V² + D/V³ + …
D. None of the above
Answer» D. None of the above
222.

_ A refrigeration cycle is the same as a __________ cycle,$?

A. Turbine
B. Heat engine
C. Reversed heat engine
D. None of these
Answer» D. None of these
223.

_ The expression, nCv(T‚ÇÇ - T‚ÇÅ), is for the __________ of an ideal gas.$?

A. Work done under adiabatic condition
B. Co-efficient of thermal expansion
C. Compressibility
D. None of these
Answer» B. Co-efficient of thermal expansion
224.

_ Pick out the correct equation relating 'F' and 'A'.$?

A. F = A + PV
B. F = E + A
C. F = A - TS
D. F = A + TS
Answer» B. F = E + A
225.

_ Fugacity is a measure of the$?

A. Escaping tendencies of the same substance in different phases of a system
B. Relative volatility of a mixture of two miscible liquids
C. Behaviour of ideal gases
D. None of these
Answer» B. Relative volatility of a mixture of two miscible liquids
226.

_ A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is Φi yi P = Yi xi fi° where, Φ is a vapor fugacity component, Yi is the liquid activity co-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of$?

A. Temperature only
B. Temperature and pressure only
C. Temperature, pressure and liquid composition xi only
D. Temperature, pressure, liquid composition xi and vapour composition yi
Answer» D. Temperature, pressure, liquid composition xi and vapour composition yi
227.

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

A. Internal energy
B. Enthalpy
C. Entropy
D. All of the above
Answer» C. Entropy
228.

_ At the absolute zero temperature, the entropy of every perfectly crystalline substance becomes zero. This follows from the$?

A. Third law of thermodynamics
B. Second law of thermodynamics
C. Nernst heat theorem
D. Maxwell's relations
Answer» B. Second law of thermodynamics
229.

_ Which of the following equations is obtained on combining 1st and 2nd law of thermodynamics, for a system of constant mass?$?

A. DE = Tds - PdV
B. DQ = CvdT + PdV
C. DQ = CpdT + Vdp
D. Tds = dE - PdV
Answer» B. DQ = CvdT + PdV
230.

_ Solubility of a substance which dissolves with an increase in volume and liberation of heat will be favoured by the$?

A. Low pressure and high temperature
B. Low pressure and low temperature
C. High pressure and low temperature
D. High pressure and high temperature
Answer» C. High pressure and low temperature
231.

_ Measurement of thermodynamic property of temperature is facilitated by __________ law of thermodynamics.$?

A. 1st
B. Zeroth
C. 3rd
D. None of these
Answer» C. 3rd
232.

_ 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
233.

_ Gibbs phase rule finds application, when heat transfer occurs by$?

A. Conduction
B. Convection
C. Radiation
D. Condensation
Answer» E.
234.

_ The relation connecting the fugacities of various components in a solution with one another and to composition at constant temperature and pressure is called the __________ equation.$?

A. Gibbs-Duhem
B. Van Laar
C. Gibbs-Helmholtz
D. Margules
Answer» B. Van Laar
235.

_ The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the$?

A. Lewis-Randall rule
B. Statement of Vant-Hoff equation
C. Le-Chatelier's principle
D. None of these
Answer» E.
236.

_ A nozzle is a device, which$?

A. Increases kinetic energy and decreases pressure
B. Reduces kinetic energy and increases pressure
C. Reduces both kinetic energy and pressure
D. Increases both kinetic energy and pressure
Answer» B. Reduces kinetic energy and increases pressure
237.

_ Trouton's ratio is given by (where λb, = molal heat of vaporisation of a substance at its normal boiling point, kcal/kmol Tb = normal boiling point, °K )$?

A. λb/Tb
B. Tb/λb
C. ‚Äö√ √∂(≈í¬™b/Tb)
D. ‚Äö√ √∂(Tb/≈í¬™b)
Answer» B. Tb/≈í¬™b
238.

_ Domestic refrigerator usually works on the __________ refrigeration cycle.$?

A. Carnot
B. Air
C. Absorption
D. Vapour-ejection
Answer» D. Vapour-ejection
239.

_ Entropy, which is a measure of the disorder of a system is$?

A. Independent of pressure
B. Independent of temperature
C. Zero at absolute zero temperature for a perfect crystalline substance
D. All of the above
Answer» D. All of the above
240.

_ Which of the following equations is used for the prediction of activity co-efficient from experiments?$?

A. Van Laar equation
B. Margules equation
C. Wilson's equation
D. All of the above
Answer» E.
241.

_ In an ideal refrigeration cycle, the change in internal energy of the fluid is$?

A. +ve
B. -ve
C. 0
D. Either of the above three ; depends on the nature of refrigerant
Answer» D. Either of the above three ; depends on the nature of refrigerant
242.

_ Which is not constant for an ideal gas?$?

A. (‚Äö√ √áP/‚Äö√ √áV)T
B. (‚Äö√ √áV/‚Äö√ √áT)P
C. (‚Äö√ √áP/‚Äö√ √áV)V
D. All of the above
Answer» B. (‚Äö√ √áV/‚Äö√ √áT)P
243.

_ 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.
244.

_ 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 of the above
Answer» C. The iceberg remains in a warmer condition at the base
245.

_ In Joule-Thomson porous plug experiment, the$?

A. Enthalpy does not remain constant
B. Entire apparatus is exposed to surroundings
C. Temperature remains constant
D. None of these
Answer» E.
246.

_ When a gas is subjected to adiabatic expansion, it gets cooled due to$?

A. Decrease in velocity
B. Decrease in temperature
C. Decrease in kinetic energy
D. Energy spent in doing work
Answer» E.
247.

__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
248.

__Gibbs free energy at constant pressure and temperature under equilibrium conditions is__

A. ‚Äö√ √ª
B. 0
C. Maximum
D. Minimum
Answer» E.
249.

__A domestic refrigerator has a/an __________ cooled condenser.__

A. Water
B. Air
C. Evaporative
D. Gas
Answer» C. Evaporative
250.

__In polytropic process (PVn = constant), if n = 1; it means a/an __________ process.__

A. Adiabatic
B. Reversible
C. Isothermal
D. None of these
Answer» D. None of these