MCQOPTIONS
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MCQOPTIONS
This section includes 591 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
*$_In case of __________ distillation, a solvent is added to alter the relative volatility of the mixture to be separated.? |
| A. | Molecular |
| B. | Azeotropic |
| C. | Extractive |
| D. | Flash |
| Answer» D. Flash | |
| 102. |
*$_To remove all the moisture from a wet solid it requires exposure to __________ air.? |
| A. | Perfectly dry |
| B. | Highly humid |
| C. | High temperature |
| D. | None of these |
| Answer» B. Highly humid | |
| 103. |
*$_Ion exchange process is similar to? |
| A. | Absorption |
| B. | Adsorption |
| C. | Extraction |
| D. | Leaching |
| Answer» C. Extraction | |
| 104. |
*$_An alkaline solution is used to reduce the concentration of carbon dioxide in a stream from 10% to 0.1% by absorption with irreversible chemical reaction. The overall number of transfer units based on gas phase is? |
| A. | 9.21 |
| B. | 4.605 |
| C. | 100 |
| D. | 0.001 |
| Answer» C. 100 | |
| 105. |
*/*_The unit of volumetric diffusivity is? |
| A. | Cm²/sec |
| B. | Cm/sec |
| C. | Cm³/sec |
| D. | Cm²/seC₂ |
| Answer» B. Cm/sec | |
| 106. |
*/*_Make up water is required in a cooling tower to replace the water lost by? |
| A. | Evaporation |
| B. | Drift |
| C. | Blowdown and leakage |
| D. | All of the above |
| Answer» E. | |
| 107. |
*/*_A binary mixture of benzene and cyclohexane is separated by? |
| A. | Flash vaporisation |
| B. | Extractive distillation |
| C. | Solvent extraction |
| D. | Ordinary distillation |
| Answer» C. Solvent extraction | |
| 108. |
*/*_In distillation, overhead product contains? |
| A. | Only one component |
| B. | Two components |
| C. | Any number of components |
| D. | Only saturated liquid |
| Answer» D. Only saturated liquid | |
| 109. |
*/*_The term "cooling range" in a cooling tower refers to the difference in the temperature of? |
| A. | Cold water leaving the tower and the wet bulb temperature of the surrounding air |
| B. | Hot water entering the tower and the wet bulb temperature of the surrounding air |
| C. | Hot water entering the tower and the cooled water leaving the tower |
| D. | None of these |
| Answer» D. None of these | |
| 110. |
*/*_At a given equilibrium pressure, with increase in temperature, the concentration of adsorbed gas on solid adsorbant? |
| A. | Increases |
| B. | Decreases |
| C. | Remains unchanged |
| D. | Increases exponentially |
| Answer» C. Remains unchanged | |
| 111. |
*/*_Diameter of raschig rings used in packed tower in industry is normally around __________ inches.? |
| A. | 2 |
| B. | 8 |
| C. | 12 |
| D. | 18 |
| Answer» B. 8 | |
| 112. |
*/*_Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in terms of __________ humidity.? |
| A. | Molal |
| B. | Relative |
| C. | Percentage |
| D. | None of these |
| Answer» B. Relative | |
| 113. |
*/*_Deairation (removal of O‚ÇÇ) of water is done by? |
| A. | Rectification |
| B. | Absorption |
| C. | Ion-exchange |
| D. | Adsorption |
| Answer» D. Adsorption | |
| 114. |
*/*_The ratio of Murphree plate efficiency to point efficiency is 1 in a __________ flow model.? |
| A. | Plug |
| B. | Perfectly mixed |
| C. | Both A & B |
| D. | Neither A nor B |
| Answer» C. Both A & B | |
| 115. |
*/*_The term "approach" in a cooling tower refers to the difference in the temperature of the? |
| A. | Cold water leaving the tower and the wet bulb temperature of the surrounding air |
| B. | Hot water entering the tower and the wet bulb temperature of the surrounding air |
| C. | Hot water entering and the cooled water leaving the cooling tower |
| D. | None of these |
| Answer» B. Hot water entering the tower and the wet bulb temperature of the surrounding air | |
| 116. |
*/*_Which of the following adsorbant is used in the refinning of sugar?? |
| A. | Bone charcoal |
| B. | Wood charcoal |
| C. | Silica gel |
| D. | Activated clay |
| Answer» B. Wood charcoal | |
| 117. |
*/*_A 25 cm x 25 cm x 1 cm flat sheet weighing 1.2 kg initially was dried from both sides under constant drying rate conditions. It took 1500 seconds for the weight of the sheet to reduce to 1.05 kg. Another 1m x 1m x 1cm flat sheet of the same material is to be dried from one side only.Under the same constant drying rate conditions, the time required for drying (in seconds) from its initial weight of 19.2 kg to 17.6 kg is? |
| A. | 1000 |
| B. | 1500 |
| C. | 2000 |
| D. | 2500 |
| Answer» B. 1500 | |
| 118. |
*/*_Sticky material can be dried in a __________ dryer.? |
| A. | Tray |
| B. | Rotary |
| C. | Fluidised bed |
| D. | None of these |
| Answer» B. Rotary | |
| 119. |
*/*_Inside the distillation column, the? |
| A. | Driving force for the vapour flow is the pressure drop |
| B. | Liquids are not always at their bubble points |
| C. | Pressure increases gradually from bottom to the top of the column |
| D. | None of these |
| Answer» B. Liquids are not always at their bubble points | |
| 120. |
*/*_In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:(i) Reflux stream is completely liquid and is at its bubble point.(ii) Reflux stream is below its bubble point.? |
| A. | Condenser and reboiler loads are the same in both the cases |
| B. | Reboiler load is the same in both the cases but condenser load is higher in case (ii) |
| C. | Condenser load is the same in both the cases but reboiler load is higher in case (ii) |
| D. | Both condensor and reboiler loads are higher in case (ii) as compared to case (i) |
| Answer» E. | |
| 121. |
*/*_The Hatta number is important in? |
| A. | Multicomponent distillation |
| B. | Binary distillation |
| C. | Gas absorption without chemical reaction |
| D. | Gas absorption with chemical reaction |
| Answer» E. | |
| 122. |
*/*_During constant rate period, the rate of drying decreases with the? |
| A. | Decrease in air temperature |
| B. | Increase in air humidity |
| C. | Both A & B |
| D. | Neither A nor B |
| Answer» D. Neither A nor B | |
| 123. |
*/*_The mass transfer co-efficient for a solid sphere of radius 'a' dissolving in a large volume of quiescent liquid, in which D is the diffusivity of solute, is? |
| A. | D/a |
| B. | D/2a |
| C. | Proportional to ‚à öD |
| D. | Dependent on the Reynolds number |
| Answer» E. | |
| 124. |
*/*_The wetted wall tower is used to determine? |
| A. | Individual mass transfer co-efficient (M.T.C.) in gaseous system |
| B. | M.T.C. of individual components in a liquid-liquid system |
| C. | M.T.C. of liquid in liquid-gas system |
| D. | The overall M.T.C. of the system |
| Answer» B. M.T.C. of individual components in a liquid-liquid system | |
| 125. |
*/*_Small dia distillation column can be a? |
| A. | Packed column |
| B. | Sieve tray |
| C. | Bubble cap |
| D. | Any of these |
| Answer» B. Sieve tray | |
| 126. |
*/*_Unsaturated air (with dry and wet bulb temperatures being 35 and 25°C respectively) is passed through water spray chamber maintained at 35°C. The air will be? |
| A. | Cooled |
| B. | Humidified |
| C. | Both A & B |
| D. | Dehumidified |
| Answer» C. Both A & B | |
| 127. |
*/*_Humid volume, at a given temperature is a/an __________ function of humidity.? |
| A. | Inverse |
| B. | Exponential |
| C. | Linear |
| D. | Logarithmic |
| Answer» D. Logarithmic | |
| 128. |
*/*_For the case of flow of air past a wet bulb thermometer (air water vapour system), the approximate value of H‚ÇÇ/ky.Cz is around? |
| A. | 0.60 |
| B. | 0.24 |
| C. | 1 |
| D. | 0.72 |
| Answer» D. 0.72 | |
| 129. |
*/*_An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii)? |
| A. | Less number of trays are required |
| B. | Composition of the residue remains unchanged |
| C. | More number of trays are required but the residue composition remains unchanged |
| D. | More number of trays are required and the residue composition is more dilute in methanol |
| Answer» B. Composition of the residue remains unchanged | |
| 130. |
*/*_Weight of 1 m³ of humid air as compared to 1 m³ of dry air, under the same conditions, is? |
| A. | Less |
| B. | More |
| C. | Same |
| D. | Unpredictable |
| Answer» B. More | |
| 131. |
*/*_An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively.The humidity of air sample expressed as kg of water vapour/kg of dry air is? |
| A. | 0.048 |
| B. | 0.079 |
| C. | 0.122 |
| D. | 0.152 |
| Answer» E. | |
| 132. |
*/*_Which of the following is not fixed by the process requirements, in the design of absorbers?? |
| A. | Flow rate of the entering gas |
| B. | Composition of the entering liquid |
| C. | Terminal concentrations of gas stream |
| D. | None of these |
| Answer» E. | |
| 133. |
*/*_In case of constant underflow extraction operation, the __________ at all solute concentration.? |
| A. | Solids are drained to the same extent |
| B. | Ratio of the insoluble to solution is constant |
| C. | Both A & B |
| D. | Neither A nor B |
| Answer» D. Neither A nor B | |
| 134. |
*/*_Dry bulb temperature of the gas is __________ the wet bulb temperature.? |
| A. | Less than |
| B. | More than |
| C. | Equal to |
| D. | None of these |
| Answer» C. Equal to | |
| 135. |
*/*_The value of Lewis number (Le = Sc/Pr) for air-water vapour system is around? |
| A. | 1 |
| B. | 0.24 |
| C. | 3.97 |
| D. | 600 |
| Answer» B. 0.24 | |
| 136. |
*/*_Danckwerts developed the __________ theory.? |
| A. | Penetration |
| B. | Surface renewal |
| C. | Film |
| D. | None of these |
| Answer» C. Film | |
| 137. |
*/*_Adsorption is an unit operation which generally involves __________ systems.? |
| A. | Liquid-solid |
| B. | Gas-solid |
| C. | Fluid-solid |
| D. | Solid-solid |
| Answer» D. Solid-solid | |
| 138. |
*/*_The rough value of diffusion co-efficient of water vapor into air at 25°C may be about __________ cm²/sec.? |
| A. | 0.25 |
| B. | 2.5 |
| C. | 1.25 |
| D. | 0.0025 |
| Answer» B. 2.5 | |
| 139. |
*/*_Pick out the wrong statement pertaining to the cooling towers.? |
| A. | In case of induced draft cooling tower, the fan is placed at the top of the tower |
| B. | Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and hot discharged air |
| C. | A natural draft cooling tower is recommended to be used, when the air humidity is low and air temperature is also low |
| D. | Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature |
| Answer» E. | |
| 140. |
*/*_The dimension of diffusivity is same as that of the? |
| A. | Density |
| B. | Molal concentration |
| C. | Kinematic viscosity |
| D. | Velocity head |
| Answer» D. Velocity head | |
| 141. |
*/*_Which of these columns incurs the lowest pressure drop?? |
| A. | Packed column (with stacked packing) |
| B. | Packed column (with dumped packing) |
| C. | Bubble plate column |
| D. | Pulse column |
| Answer» B. Packed column (with dumped packing) | |
| 142. |
*/*_Equilibrium-moisture curves of different solids? |
| A. | Are different |
| B. | Are same |
| C. | Depend on the humidity of the gas |
| D. | None of these |
| Answer» B. Are same | |
| 143. |
*/*_The operating cost of a distillation column at minimum reflux ratio is? |
| A. | Minimum |
| B. | Maximum |
| C. | Infinite |
| D. | Zero |
| Answer» B. Maximum | |
| 144. |
*/*_The dew point of an unsaturated gas-vapor mixture does not depend upon the __________ of the mixture.? |
| A. | Composition |
| B. | Temperature |
| C. | Total pressure |
| D. | All of the above |
| Answer» C. Total pressure | |
| 145. |
*/*_For a ternery mixture, in which equilateral triangular co-ordinate is used in leaching and extraction, a __________ of the equilateral triangular co-ordinates.? |
| A. | Binary mixture is represented by the apex |
| B. | Binary mixture is represented by any point inside |
| C. | Ternery mixture is represented by the sides |
| D. | Pure component is represented by the apex |
| Answer» E. | |
| 146. |
*/*_Detergent solution is dried to a powder in a? |
| A. | Spray dryer |
| B. | Spouted bed dryer |
| C. | Tunnel dryer |
| D. | Pan open to atmosphere |
| Answer» B. Spouted bed dryer | |
| 147. |
*/*_In McCabe-Thiele method, at infinite reflux ratio? |
| A. | The overhead product is minimum |
| B. | Both the operating lines coincide with diagonal |
| C. | Both A & B |
| D. | Neither A nor B |
| Answer» B. Both the operating lines coincide with diagonal | |
| 148. |
*/*_A liquid mixture contains 30% o-xylene, 60% p-xylene and 10%. m-xylene (all percentages in w/w). Which of the following statements would be true in respect of this mixture?? |
| A. | The mixture exhibits an azeotrope at 101.3 kPa |
| B. | The composition of the mixture, in percent by volume is: o-xylene 30, p-xylene 60. and m-xylene 10 |
| C. | The composition of the mixture in mole percent is: o-xylene 30, p-xylene 60 and m-xyoene 10 |
| D. | The mixture contain optical isomers |
| Answer» B. The composition of the mixture, in percent by volume is: o-xylene 30, p-xylene 60. and m-xylene 10 | |
| 149. |
*/*_For the air water system under ambient conditions, the adiabatic saturation temperature and the wet bulb temperature are nearly equal, because? |
| A. | Water has a high latent heat of evaporation |
| B. | Lewis number is close to unity |
| C. | They are always equal under all circumstances |
| D. | Solubility of the components of air in water is very small |
| Answer» B. Lewis number is close to unity | |
| 150. |
*/*_The McCabe Δ L law states that the? |
| A. | Molar heats of vaporisation of components are nearly equal |
| B. | Linear crystal growth rate depends on the degree of supersaturation |
| C. | Linear crystal growth rate does not depend on the crystal size |
| D. | Linear crystal growth rate depends on the crystal size |
| Answer» D. Linear crystal growth rate depends on the crystal size | |