MCQOPTIONS
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MCQOPTIONS
This section includes 8247 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 2301. |
Large quantity of silica gel is normally dried in a __________ dryer. |
| A. | freeze |
| B. | through circulation |
| C. | rotary vacuum |
| D. | tray |
| Answer» C. rotary vacuum | |
| 2302. |
For the same system, if the same liquid used in an absorber is decreased, the tower height will |
| A. | increase |
| B. | decrease |
| C. | remain unaffected |
| D. | decrease or increase ; depends on the type of liquid |
| Answer» B. decrease | |
| 2303. |
Radioactive nuclear waste is treated in |
| A. | mixer-settler extractor |
| B. | rotating-disc contactor |
| C. | pulsed column extractor |
| D. | Bollman extractor |
| Answer» D. Bollman extractor | |
| 2304. |
Large scale drying of sugar is done in a __________ dryer. |
| A. | spouted bed |
| B. | tray |
| C. | rotary |
| D. | truck |
| Answer» D. truck | |
| 2305. |
__________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gas-vapor mixture. |
| A. | Dry bulb |
| B. | Wet bulb |
| C. | Dew point |
| D. | none of these |
| Answer» C. Dew point | |
| 2306. |
__________ equation applies to diffusivities in liquids. |
| A. | Gilliland |
| B. | Hirschfelder |
| C. | Wilke and Chang |
| D. | none of these |
| Answer» B. Hirschfelder | |
| 2307. |
Molecular seives are regenerated by heating to __________ C. |
| A. | < 150 |
| B. | 200-330 |
| C. | > 500 |
| D. | > 1000 |
| Answer» C. > 500 | |
| 2308. |
Which of the following equipments is not used for gas dispersion ? |
| A. | Agitated vessels |
| B. | Bubble cap tray towers |
| C. | Perforated sieve tray towers |
| D. | Spray towers |
| Answer» E. | |
| 2309. |
One mole feed of a binary mixture of a given composition is flash vaporised at a fixed P and T. If Raoult's law is obeyed, then changing the feed composition would effect |
| A. | the product composition but not the fraction vaporised. |
| B. | the product composition as well as the fraction vaporised. |
| C. | the fraction vaporised but not the product composition. |
| D. | neither the product composition nor the fraction vaporised. |
| Answer» D. neither the product composition nor the fraction vaporised. | |
| 2310. |
The equation, is for |
| A. | steady state equimolar counter diffusion |
| B. | Fick's first law of diffusion |
| C. | steady state diffusion for stagnant case |
| D. | liquid M.T.C. by penetration theory. |
| Answer» B. Fick's first law of diffusion | |
| 2311. |
With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop |
| A. | decreases |
| B. | remains unchanged |
| C. | increases |
| D. | decreases exponentially |
| Answer» D. decreases exponentially | |
| 2312. |
The equation, is for |
| A. | Fick's second law of diffusion. |
| B. | stready state diffusion for stagnant case. |
| C. | liquid M.T.C. by Higbie penetration theory. |
| D. | none of these. |
| Answer» C. liquid M.T.C. by Higbie penetration theory. | |
| 2313. |
A distillation column separates 10000 kg/hr of a benzene-toluene mixture as shown in the figure below : In the figure xF, xD and xW represent the weight fraction of benzene in the feed, distillate and residue respectively. The reflux ratio is |
| A. | 0.5 |
| B. | 0.6 |
| C. | 1.0 |
| D. | 2.0 |
| Answer» C. 1.0 | |
| 2314. |
Unsaturated air (with dry bulb and wet bulb temperatures being 45 C and 25 C respectively) is passed through a water spray chamber maintained at 23 C. The air will be cooled and |
| A. | humidified with wet bulb temperature decreasing. |
| B. | humidified at constant wet bulb temperature. |
| C. | dehumidified. |
| D. | none of these |
| Answer» B. humidified at constant wet bulb temperature. | |
| 2315. |
Humid volume, at a given temperature is a/an __________ function of humidity. |
| A. | inverse |
| B. | exponential |
| C. | linear |
| D. | logarithmic |
| Answer» D. logarithmic | |
| 2316. |
In a packed bed absorption column, the channelling will be noted by the |
| A. | increase in flow rate. |
| B. | sharp drop in pressure drop. |
| C. | sharp rise in pressure drop. |
| D. | none of these. |
| Answer» C. sharp rise in pressure drop. | |
| 2317. |
Gaseous diffusivity at atmospheric pressure is of the order of __________ cm2/second. |
| A. | 1 |
| B. | 1 to 5 |
| C. | 5 to 10 |
| D. | > 10 |
| Answer» B. 1 to 5 | |
| 2318. |
In liquid-liquid extraction, the number of phases at plait point is |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» B. 2 | |
| 2319. |
Humid volume is the total volume in m3 of 1 kg of |
| A. | vapour laden gas at 1 atm. and room temperature. |
| B. | gas plus its accompanying vapour at 1 atm. and room temperature. |
| C. | gas plus its accompanying vapour at 1 atm. and gas temperature. |
| D. | vapour laden gas at 1 atm. and gas temperature. |
| Answer» D. vapour laden gas at 1 atm. and gas temperature. | |
| 2320. |
Diameter to height ratio for a rashig ring is |
| A. | 1 |
| B. | 0.5 |
| C. | 2 |
| D. | 8 |
| Answer» B. 0.5 | |
| 2321. |
The equipment used in the extraction of highly corrosive radio active liquids is |
| A. | pulse column |
| B. | spray column |
| C. | mixer settler |
| D. | baffle tower |
| Answer» B. spray column | |
| 2322. |
Advantage of continuous drying over batch drying is that the |
| A. | drying cost per unit weight of dried product is less. |
| B. | product with more uniform moisture content is produced. |
| C. | equipment size required is smaller. |
| D. | all 'a', 'b' & 'c' |
| Answer» E. | |
| 2323. |
In a liquid-liquid extraction, 10 kg of a solution containing 2 kg of solute C and 8 kg of solvent A is brought into contact with 10 kg of solvent B. Solvent A and B are completely immiscible in each other whereas solute C is soluble in both the solvents. The extraction process attains equilibrium. The equilibrium relationship between the two phases is Y* = 0.9X, where Y* is the kg of C/kg of B and X is kg of C/kg of A. Choose the correct answer. |
| A. | The entire amount of C is transferred to solvent B. |
| B. | Less than 2 kg but more than 1 kg of C is transferred to solvent B. |
| C. | Less than 1 kg of C is transferred to B. |
| D. | No amount of C is tranferred to B. |
| Answer» B. Less than 2 kg but more than 1 kg of C is transferred to solvent B. | |
| 2324. |
With increase in temperature, the rate of extraction in leaching (solid-liquid extraction system) |
| A. | increases |
| B. | decreases |
| C. | remains unaffected |
| D. | increases Linearly |
| Answer» B. decreases | |
| 2325. |
Mass transfer co-efficient is directly proportional to DAB0.5, according to __________ theory. |
| A. | penetration |
| B. | surface renewal |
| C. | film |
| D. | none of these |
| Answer» B. surface renewal | |
| 2326. |
Sand is dried in foundaries in a___drier. |
| A. | rotary |
| B. | fluidisedbed |
| C. | vacuum |
| D. | spray |
| Answer» C. vacuum | |
| 2327. |
The expression, y(1 - x)/x(1 - y) is for |
| A. | absorption factor |
| B. | relative volatility |
| C. | selectivity |
| D. | Murphree efficiency |
| Answer» C. selectivity | |
| 2328. |
Which of the following employs an accessory known as 'drift eliminator' ? |
| A. | Multiple effect evaporator. |
| B. | Mechanical draft cooling tower. |
| C. | Rotary dryer. |
| D. | Rotating disc contactor. |
| Answer» C. Rotary dryer. | |
| 2329. |
__________ number indicates the ratio of the rates of the heat and mass transfer incase of a cooling tower. |
| A. | Sherwood |
| B. | Stanton |
| C. | Lewis |
| D. | Peclet |
| Answer» D. Peclet | |
| 2330. |
In physical terms, Schmidt number means |
| A. | thermal diffusivity/mass diffusivity. |
| B. | thermal diffusivity/momentum diffusivity. |
| C. | momentum diffusivity/mass diffusivity. |
| D. | mass diffusivity/thermal diffusivity. |
| Answer» D. mass diffusivity/thermal diffusivity. | |
| 2331. |
The diffusivity, DAB (for component A diffusing in B) is equal to the diffusivity DBA (for component B diffusing in A) for a binary mixture of |
| A. | Newtonion liquids |
| B. | non-Newtonion liquids |
| C. | ideal gases |
| D. | real gases |
| Answer» D. real gases | |
| 2332. |
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 | |
| 2333. |
In case of non-ideal gases and liquids, the molal diffusivity |
| A. | varies inversely as the pressure. |
| B. | varies directly as the pressure. |
| C. | is independent of pressure. |
| D. | is equal to the volumetric diffusivity. |
| Answer» D. is equal to the volumetric diffusivity. | |
| 2334. |
Which of the following is not a unit of mass transfer co-efficient ? |
| A. | <img src="/_files/images/chemical-engineering/mass-transfer/296-219-1.png"> |
| B. | <img src="/_files/images/chemical-engineering/mass-transfer/296-219-2.png"> |
| C. | <img src="/_files/images/chemical-engineering/mass-transfer/296-219-3.png"> |
| D. | None of these |
| Answer» E. | |
| 2335. |
The falling rate period in the drying of a solid is characterised by |
| A. | increase in rate of drying. |
| B. | increasing temperatures both on the surface and within the solid. |
| C. | decreasing temperatures. |
| D. | none of these. |
| Answer» C. decreasing temperatures. | |
| 2336. |
In which of the following unit operations, the selectivity is an important parameter ? |
| A. | Distillation |
| B. | Solvent extraction |
| C. | Absorption |
| D. | None of these |
| Answer» C. Absorption | |
| 2337. |
Which of the following equipments is not used for liquid dispersion ? |
| A. | Wetted wall towers |
| B. | Packed towers |
| C. | Venturi scrubbers |
| D. | Agitated vessels |
| Answer» E. | |
| 2338. |
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 | |
| 2339. |
Which of the following adsorbent is used to decolourise yellow glycerine ? |
| A. | Silica gel |
| B. | Alumina |
| C. | Fuller's earth |
| D. | Activated carbon |
| Answer» E. | |
| 2340. |
Which of the following liquid temperature (T) Vs. vapor-gas mixture enthalpy (H) diagram is valid for humidification operation? |
| A. | <img src="/_files/images/chemical-engineering/mass-transfer/317-499-1.png"> |
| B. | <img src="/_files/images/chemical-engineering/mass-transfer/317-499-2.png"> |
| C. | <img src="/_files/images/chemical-engineering/mass-transfer/317-499-3.png"> |
| D. | none of these. |
| Answer» C. <img src="/_files/images/chemical-engineering/mass-transfer/317-499-3.png"> | |
| 2341. |
Which of the following is an undesirable characteristic for the solvent used in gas absorption ? |
| A. | Low vapor pressure |
| B. | Low viscosity |
| C. | High gas solubility |
| D. | None of these |
| Answer» E. | |
| 2342. |
In a distillation column, with increase in the reflux ratio, the heat removed in the cooler |
| A. | increases. |
| B. | decreases. |
| C. | remains unaffected. |
| D. | and the heat required in reboiler decreases. |
| Answer» B. decreases. | |
| 2343. |
In case of absorption, both the operating and equilibrium lines will be straight for |
| A. | isothermal operation. |
| B. | dilute solutions. |
| C. | dilute solutions and isothermal operation. |
| D. | none of these. |
| Answer» D. none of these. | |
| 2344. |
The Schmidt number which is defined as, / D, is the ratio of the |
| A. | momentum diffusivity to the mass dif-fusivity. |
| B. | thermal diffusivity to the mass diffusivity. |
| C. | momentum diffusivity to the thermal diffusivity. |
| D. | none of these. |
| Answer» B. thermal diffusivity to the mass diffusivity. | |
| 2345. |
If Rm is the minimum reflux ratio, the optimum reflux ratio may be around __________ Rm. |
| A. | 1.2 to 1.5 |
| B. | 2.5 to 3 |
| C. | 3 to 4 |
| D. | 5 |
| Answer» B. 2.5 to 3 | |
| 2346. |
During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains constant. |
| A. | wet bulb temperature |
| B. | partial pressure of water vapor |
| C. | relative humidity |
| D. | none of these |
| Answer» B. partial pressure of water vapor | |
| 2347. |
Mass transfer co-efficient varies as DAB0.5, according to the __________ theory. |
| A. | film |
| B. | surface renewal |
| C. | penetration |
| D. | none of these |
| Answer» C. penetration | |
| 2348. |
For an absorber, both equilibrium and operating line will be straight for |
| A. | concentrated solution and non-isothermal operation. |
| B. | dilute solution and non-isothermal operation. |
| C. | dilute solution and isothermal operation. |
| D. | concentrated solution and isothermal operation. |
| Answer» D. concentrated solution and isothermal operation. | |
| 2349. |
In a counter-current extractor, as the axial mixing increases, the extraction efficiency |
| A. | increases |
| B. | decreases |
| C. | remains unchanged |
| D. | depends on the pressure of the system |
| Answer» C. remains unchanged | |
| 2350. |
Heat sensitive materials like certain pharmaceuticals and food stuffs can be dried in a/an __________ dryer. |
| A. | indirect tray |
| B. | spray |
| C. | freeze |
| D. | none of these |
| Answer» D. none of these | |