MCQOPTIONS
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MCQOPTIONS
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.
| 451. |
The quantitative effect of temperature on chemical equilibrium is given by the |
| A. | Vant-Hoff equation. |
| B. | Le-Chatelier's principle. |
| C. | Arhenius equation. |
| D. | none of these. |
| Answer» B. Le-Chatelier's principle. | |
| 452. |
Sublimation temperature of dry ice (solid CO2) is __________ °C.$ |
| A. | -273 |
| B. | 0 |
| C. | -78 |
| D. | 5 |
| Answer» D. 5 | |
| 453. |
In the ammonia synthesis reaction, N2 + 3H2 2NH3 + 22.4 kcal, the formation of NH3 will be favoured by |
| A. | high temperature. |
| B. | low pressure. |
| C. | low temperature only. |
| D. | both low temperature and high pressure. |
| Answer» E. | |
| 454. |
Entropy of a substance remains constant during a/an __________ change. |
| A. | reversible isothermal |
| B. | irreversible isothermal |
| C. | reversible adiabatic |
| D. | none of these |
| Answer» D. none of these | |
| 455. |
PVγ = Constant (where, γ = Cp/Cv) is valid for a/an __________ process.$ |
| A. | isothermal |
| B. | isentropic |
| C. | isobaric |
| D. | adiabatic |
| Answer» E. | |
| 456. |
A Carnot cycle consists of the following steps : |
| A. | Two isothermals and two isentropics. |
| B. | Two isobarics and two isothermals. |
| C. | Two isochorics and two isobarics. |
| D. | Two isothermals and two isochorics. |
| Answer» B. Two isobarics and two isothermals. | |
| 457. |
Any substance above its critical temperature exists as |
| A. | saturated vapour |
| B. | solid |
| C. | gas |
| D. | liquid |
| Answer» D. liquid | |
| 458. |
For an ideal gas, the activity co-efficient is |
| A. | directly proportional to pressure. |
| B. | inversely proportional to pressure. |
| C. | unity at all pressures. |
| D. | none of these. |
| Answer» D. none of these. | |
| 459. |
For any system, what is the minimum number of degrees of freedom? |
| A. | 1 |
| B. | 0 |
| C. | 2 |
| D. | 3 |
| Answer» C. 2 | |
| 460. |
Domestic refrigerator usually works on the __________ refrigeration cycle. |
| A. | Carnot |
| B. | air |
| C. | absorption |
| D. | vapour-ejection |
| Answer» D. vapour-ejection | |
| 461. |
What is the degree of freedom for a system comprising liquid water equilibrium with its vapour ? |
| A. | 0 |
| B. | 1 |
| C. | 2 |
| D. | 3 |
| Answer» C. 2 | |
| 462. |
A gas mixture of three components is brought in contact with a dispersion of an organic phase in water. The degree of freedom of the system are |
| A. | 4 |
| B. | 3 |
| C. | 5 |
| D. | 6 |
| Answer» C. 5 | |
| 463. |
At constant temperature and pressure, for one mole of a pure substance, the ratio of the free energy to the chemical potential is |
| A. | zero |
| B. | one |
| C. | infinity |
| D. | negative |
| Answer» C. infinity | |
| 464. |
For an ideal gas, the chemical potential is given by |
| A. | RT dlnP |
| B. | R dlnP |
| C. | R dlnf |
| D. | none of these |
| Answer» B. R dlnP | |
| 465. |
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. | |
| 466. |
As the entropy of the universe is increasing, day by day, the work producing capacity of a heat engine is |
| A. | not changed |
| B. | decreasing |
| C. | increasing |
| D. | data sufficient, can't be predicted |
| Answer» C. increasing | |
| 467. |
For a constant volume process |
| A. | dE = CpdT |
| B. | dE = CvdT |
| C. | dQ = dE + pdV |
| D. | dW = pdV |
| Answer» C. dQ = dE + pdV | |
| 468. |
A system is said to be isopiestic, if there is no __________ change. |
| A. | temperature |
| B. | pressure |
| C. | volume |
| D. | none of these |
| Answer» C. volume | |
| 469. |
The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the __________ of a substance.$ |
| A. | simultaneous pressure & temperature change |
| B. | heating |
| C. | cooling |
| D. | both (b) and (c) |
| Answer» E. | |
| 470. |
The necessary condition for phase equilibrium in a multiphase system of N components is that the |
| A. | chemical potentials of a given component should be equal in all phases. |
| B. | chemical potentials of all components should be same in a particular phase. |
| C. | sum of the chemical potentials of any given component in all the phases should be the same. |
| D. | none of these. |
| Answer» B. chemical potentials of all components should be same in a particular phase. | |
| 471. |
With increase in pressure (above atmospheric pressure), the Cp of a gas |
| A. | increases |
| B. | decreases |
| C. | remains unchanged |
| D. | first decreases and then increases |
| Answer» B. decreases | |
| 472. |
Second law of thermodynamics is concerned with the |
| A. | amount of energy transferred. |
| B. | direction of energy transfer. |
| C. | irreversible processes only. |
| D. | non-cyclic processes only. |
| Answer» C. irreversible processes only. | |
| 473. |
If we increase the pressure on a substance (which is at its triple point), then the triple point |
| A. | increases |
| B. | decreases |
| C. | remains unchanged |
| D. | may increase or decrease ; depends on the substance |
| Answer» D. may increase or decrease ; depends on the substance | |
| 474. |
The following heat engine produces power of 100000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is |
| A. | 100, 000 kW |
| B. | 160, 000 kW |
| C. | 200, 000 kW |
| D. | 320, 000 kW |
| Answer» E. | |
| 475. |
In reactions involving solids and liquids (where change in volume is negligible), the heat of reaction at constant pressure as compared to that at constant volume is |
| A. | more |
| B. | less |
| C. | same |
| D. | unpredictable; depends on the particular reaction |
| Answer» D. unpredictable; depends on the particular reaction | |
| 476. |
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 (a), (b) and (c) |
| Answer» E. | |
| 477. |
At absolute zero temperature, all substances have the same |
| A. | heat capacity |
| B. | crystalline structure |
| C. | entropy |
| D. | none of these |
| Answer» B. crystalline structure | |
| 478. |
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 (a), (b) & (c) |
| Answer» D. all (a), (b) & (c) | |
| 479. |
Equation which relates pressure, volume and temperature of a gas is called the |
| A. | equation of state |
| B. | Gibbs Duhem equation |
| C. | ideal gas equation |
| D. | none of these |
| Answer» B. Gibbs Duhem equation | |
| 480. |
Standard temperature and pressure (S.T.P.) is |
| A. | 0°C and 750 mm Hg |
| B. | 15°C and 750 mm Hg |
| C. | 0°C and 1 kgf/cm2 |
| D. | 15°C and 1 kgf/cm2 |
| Answer» B. 15¬∞C and 750 mm Hg | |
| 481. |
A system in which there is exchange of energy but not of mass, is called a/an __________ system. |
| A. | isolated |
| B. | open |
| C. | insulated |
| D. | closed |
| Answer» E. | |
| 482. |
The gas law (PV = RT) is true for an __________ change. |
| A. | isothermal |
| B. | adiabatic |
| C. | both (a) & (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 483. |
During adiabatic expansion of gas |
| A. | pressure remains constant. |
| B. | pressure is increased. |
| C. | temperature remains constant. |
| D. | none of these. |
| Answer» E. | |
| 484. |
Gibbs free energy of mixing at constant pressure and temperature is always |
| A. | 0 |
| B. | ‚àû |
| C. | #NAME? |
| D. | #NAME? |
| Answer» E. | |
| 485. |
The necessary and sufficient condition for equilibrium between two phases is |
| A. | the concentration of each component should be same in the two phases. |
| B. | the temperature of each phase should be same. |
| C. | the pressure should be same in the two phases. |
| D. | the chemical potential of each component should be same in the two phases. |
| Answer» E. | |
| 486. |
Which is an example of closed system ? |
| A. | Air compressor |
| B. | Lquid cooling system of an automobile |
| C. | Boiler |
| D. | None of these |
| Answer» C. Boiler | |
| 487. |
If atmospheric temperature and dew point are nearly equal, then the relative humidity is |
| A. | zero |
| B. | 0.5 |
| C. | almost 100% |
| D. | unpredictable |
| Answer» D. unpredictable | |
| 488. |
Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a |
| A. | straight line |
| B. | sine curve |
| C. | parabola |
| D. | hyperbola |
| Answer» B. sine curve | |
| 489. |
All gases except __________ shows a cooling effect during throttling process at atmospheric temperature and pressure. |
| A. | oxygen |
| B. | nitrogen |
| C. | air |
| D. | hydrogen |
| Answer» E. | |
| 490. |
In a homogeneous solution, the activity co-efficient of a component depends upon the |
| A. | pressure |
| B. | composition |
| C. | temperature |
| D. | all (a), (b) and (c) |
| Answer» E. | |
| 491. |
What is the number of degree of freedom for a system of two miscible non-reacting species in vapor-liquid equilibrium forming an azeotrope ? |
| A. | 3 |
| B. | 2 |
| C. | 1 |
| D. | 0 |
| Answer» D. 0 | |
| 492. |
A cyclic engine exchanges heat with two reservoirs maintained at 100 and 300°C respectively. The maximum work (in J) that can be obtained from 1000 J of heat extracted from the hot reservoir is$ |
| A. | 349 |
| B. | 651 |
| C. | 667 |
| D. | 1000 |
| Answer» B. 651 | |
| 493. |
Those solutions in which there is no volume change upon mixing the components in the liquid state and which, when diluted do not undergo any heat change (i.e. heat of dilution is zero), are called __________ solutions. |
| A. | ideal |
| B. | real |
| C. | isotonic |
| D. | none of these |
| Answer» B. real | |
| 494. |
'The fugacity of a gas in a mixture is equal to the product of its mole fraction and its fugacity in the pure state at the total pressure of the mixture". This is |
| A. | the statement as per Gibbs-Helmholtz |
| B. | called Lewis-Randall rule |
| C. | Henry's law |
| D. | none of these |
| Answer» C. Henry's law | |
| 495. |
Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The reatio of chemical potential to free energy of a pure substance at oconstant temperature and pressure is |
| A. | 0 |
| B. | 1 |
| C. | ‚àû |
| D. | none of these |
| Answer» C. ‚àû | |
| 496. |
Air-refrigeration cycle |
| A. | is the most efficient of all refrigeration cycles. |
| B. | has very low efficiency. |
| C. | requires relatively large quantities of air to achieve a significant amount of refrigeration. |
| D. | both (b) and (c). |
| Answer» E. | |
| 497. |
Chemical engineering thermodynamics is concerned with the __________ in/of chemical processes. |
| A. | reaction mechanism |
| B. | calculation of rates |
| C. | energy transformation from one form to the another |
| D. | none of these |
| Answer» D. none of these | |
| 498. |
For a multicomponent system, the term chemical potential is equivalent to the |
| A. | molal concentration difference. |
| B. | molar free energy. |
| C. | partial molar free energy. |
| D. | molar free energy change. |
| Answer» D. molar free energy change. | |
| 499. |
What happens in a reversible adiabatic expansion process ? |
| A. | Heating takes place. |
| B. | Cooling takes place. |
| C. | Pressure is constant. |
| D. | Temperature is constant. |
| Answer» C. Pressure is constant. | |
| 500. |
Gibbs-Helmholtz equation is |
| A. | |
| B. | ΔF = ΔH - TΔT |
| Answer» B. ŒîF = ŒîH - TŒîT | |