MCQOPTIONS
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MCQOPTIONS
This section includes 552 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Vacuum is applied in __________ zone, in case of a general type continuous rotary drum vacuum filter. |
| A. | filtering |
| B. | washing |
| C. | drying |
| D. | all (a), (b) & (c) |
| Answer» E. | |
| 252. |
During size reduction by a jaw crusher, the energy consumed decreases with the |
| A. | decreasing size of product at constant size of feed. |
| B. | decreasing machine capacity. |
| C. | increasing size of feed at constant reduction ratio. |
| D. | none of these. |
| Answer» D. none of these. | |
| 253. |
Supporting legs of a plate and frame filter is normally made of |
| A. | stainless steel |
| B. | cast iron |
| C. | high speed steel |
| D. | wooden plank |
| Answer» C. high speed steel | |
| 254. |
A gravity decanter is meant for the separation of two __________ density. |
| A. | immiscible liquids of different |
| B. | miscible liquids of different |
| C. | immiscible liquids of same |
| D. | miscible liquids of same |
| Answer» B. miscible liquids of different | |
| 255. |
Gummy & sticky materials like molasses, sugar etc. are best transported/handled by using a __________ conveyor. |
| A. | drag |
| B. | ribbon |
| C. | screw |
| D. | slat |
| Answer» C. screw | |
| 256. |
Mixing of light fine powder such as insecticides is done by |
| A. | banbery mixer |
| B. | pug mill |
| C. | impact wheels |
| D. | kneader |
| Answer» D. kneader | |
| 257. |
Screen capacity is proportional to (where, S = screen aperture) |
| A. | S |
| B. | 1/S |
| C. | S2 |
| D. | S |
| Answer» B. 1/S | |
| 258. |
Dust laden air can be purified using a |
| A. | cyclone separator |
| B. | bag filter |
| C. | gravity settler |
| D. | tubular centrifuge |
| Answer» B. bag filter | |
| 259. |
Screen capacity is not a function of |
| A. | its openings size. |
| B. | screening mechanism. |
| C. | screening surface. |
| D. | atmospheric humidity. |
| Answer» E. | |
| 260. |
A pebble mill |
| A. | is a ball mill. |
| B. | employs flints or ceramic pebbles as the grinding medium. |
| C. | is a tube mill lined with ceramic or other non-metallic liner. |
| D. | both (b) and (c). |
| Answer» E. | |
| 261. |
Which one is a filter aid ? |
| A. | Convas fabric |
| B. | Diatomaceous earth |
| C. | Calcined lime |
| D. | None of these |
| Answer» C. Calcined lime | |
| 262. |
Which of the following can be most effectively used for clarification of lube oil and printing ink? |
| A. | Sparkler filter |
| B. | Precoat filter |
| C. | Disc-bowl centrifuge |
| D. | Sharpies supercentrifuge |
| Answer» E. | |
| 263. |
Pulverised coal passing through 200 mesh screen has a diameter of 0.074 mm (74 micron). The same passing through 50 mesh screen will have a dia of __________ mm. |
| A. | 0.007 |
| B. | 0.3 |
| C. | 50 |
| D. | 0.014 |
| Answer» C. 50 | |
| 264. |
In coal washeries, three products namely the valuable product (i.e. clean/washed coal), discarded product (i.e. mineral matter) and an additional concentrated product called __________ is produced. |
| A. | concentrate |
| B. | tailing |
| C. | middling |
| D. | none of these. |
| Answer» D. none of these. | |
| 265. |
Filtration should be stopped in a filter press, if the |
| A. | cake becomes very dense. |
| B. | liquor stops flowing out to the discharge. |
| C. | filtration pressure rises suddenly. |
| D. | both(b)&(c). |
| Answer» E. | |
| 266. |
For a cyclone of diameter 0.2 m with a tangential velocity of 15 m/s at the wall, the separation factor is |
| A. | 2250 |
| B. | 1125 |
| C. | 460 |
| D. | 230 |
| Answer» E. | |
| 267. |
Filter medium resistance is that offered by the |
| A. | filter cloth. |
| B. | embedded particles in the septum. |
| C. | filter cloth and the embedded particle collectively. |
| D. | none of these. |
| Answer» D. none of these. | |
| 268. |
A compressible cake has the |
| A. | maximum porosity at the upstream side. |
| B. | maximum porosity at the filter medium. |
| C. | same porosity throughout the cake thickness. |
| D. | none of these. |
| Answer» B. maximum porosity at the filter medium. | |
| 269. |
Reciprocal of sphericity is termed as the |
| A. | specific surface ratio |
| B. | shape factor |
| C. | sauter diameter |
| D. | surface area per unit mass |
| Answer» C. sauter diameter | |
| 270. |
Filtration rate does not depend upon the |
| A. | pressure drop & area of filtering surface. |
| B. | resistance of the cake & the septum. |
| C. | properties of the cake & the filtrate. |
| D. | none of these. |
| Answer» E. | |
| 271. |
Molten ammonium nitrate is mixed with ground limestone in fertilizer plant in a |
| A. | pug mill |
| B. | mixer-extruder |
| C. | banbury mixer |
| D. | muller mixer |
| Answer» B. mixer-extruder | |
| 272. |
For coarse reduction of hard solids, use |
| A. | impact |
| B. | attrition |
| C. | compression |
| D. | cutting |
| Answer» D. cutting | |
| 273. |
Which of the following is not a revolving/tumbling mill used for size reduction? |
| A. | Compartment mill |
| B. | Pebble mill |
| C. | Cage mill |
| D. | Rod mill |
| Answer» D. Rod mill | |
| 274. |
Which of the following crushers can be considered as a combination of a jaw crusher and a roller crusher ? |
| A. | Rod mill |
| B. | Fluid energy mill |
| C. | Gyratory crusher |
| D. | Ball mill |
| Answer» D. Ball mill | |
| 275. |
The reduction ratio for grinders is defined as(where, Df and Dp are average diameters of feed and product respectively). |
| A. | Df/Dp |
| B. | Dp/Df |
| C. | Df - Dp |
| D. | none of these |
| Answer» B. Dp/Df | |
| 276. |
Weber number is significant and is concerned with the |
| A. | solid-liquid mixing. |
| B. | liquid-liquid mixing. |
| C. | dispersion of liquid in liquid. |
| D. | suspension of solid in liquid. |
| Answer» D. suspension of solid in liquid. | |
| 277. |
Trommels are revolving screens which normally operate in the range of __________ rpm. |
| A. | 43497 |
| B. | 15 - 20 |
| C. | 40 - 50 |
| D. | 60 - 75 |
| Answer» C. 40 - 50 | |
| 278. |
Laminar flow region is said to exist during agitation of a liquid in an agitator, when the value of Reynolds number is |
| A. | >10 |
| B. | <10 |
| C. | >100 |
| D. | <100 |
| Answer» C. >100 | |
| 279. |
The optimum moisture content in solids to be crushed/ground ranges from __________ percent. |
| A. | 3 to 4 |
| B. | 8 to 10 |
| C. | 10 to 15 |
| D. | 15 to 20 |
| Answer» B. 8 to 10 | |
| 280. |
Trommels employ __________ for screening of materials. |
| A. | fibrous cloth |
| B. | woven wire screen |
| C. | punched plate |
| D. | none of these |
| Answer» D. none of these | |
| 281. |
Tabling process used for separating two materials of different densities by passing the dilute pulp over a table/deck, which is inclined from the horizontal surface at an angle of about |
| A. | 1 to 2° |
| B. | 2 to 5° |
| C. | 5 to 10° |
| D. | 10 to 15° |
| Answer» C. 5 to 10¬∞ | |
| 282. |
As the product becomes finer, the energy required for grinding |
| A. | decreases |
| B. | increases |
| C. | is same as for coarser grinding |
| D. | is 1.5 times that for coarser grinding |
| Answer» C. is same as for coarser grinding | |
| 283. |
Coal is finally pulverised to 200 mesh size for burning in boilers by a |
| A. | hammer crusher |
| B. | ball mill |
| C. | roll crusher |
| D. | gyratory crusher |
| Answer» C. roll crusher | |
| 284. |
A screen is said to be blinded, when the |
| A. | oversizes are present in undersize fraction. |
| B. | undersizes are retained in oversize fraction. |
| C. | screen is plugged with solid particles. |
| D. | screen capacity is abruptly increased. |
| Answer» D. screen capacity is abruptly increased. | |
| 285. |
Separation of materials of the same density based on their sizes by using then-different rates of flow is called |
| A. | sorting |
| B. | sizing |
| C. | flocculation |
| D. | elutriation |
| Answer» C. flocculation | |
| 286. |
Bond crushing law |
| A. | calls for relatively less energy for the smaller product particles, than does the Rittinger law. |
| B. | is less realistic in estimating the power requirements of commercial crushers. |
| C. | states that the work required to form particle of any size from very large feed is proportional to the square root of the volume to surface ratio of the product. |
| D. | states that the work required for the crushing is proportional to the new surface created. |
| Answer» B. is less realistic in estimating the power requirements of commercial crushers. | |
| 287. |
A. __________ mill is a revolving mill divided into two or more sections by perforated partitions in which preliminary grinding takes place at one end and the finishing grinding at the discharge end. |
| A. | compartment |
| B. | tube |
| C. | rod |
| D. | pebble. |
| Answer» B. tube | |
| 288. |
Addition of filter aid to the slurry before filtration is done to ...... of the cake. |
| A. | increase the porosity |
| B. | increase the compressibility co-efficient |
| C. | decrease the porosity |
| D. | decrease the compressibility co-efficient |
| Answer» B. increase the compressibility co-efficient | |
| 289. |
Specific surface area is the surface area of a unit __________ of materials. |
| A. | weight |
| B. | volume |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 290. |
__________ is used for producing a thick suspension from a thin slurry. |
| A. | Cartridge filter |
| B. | Rotary drum vacuum filter |
| C. | Pressure filter thickener |
| D. | Plate and frame filter press |
| Answer» D. Plate and frame filter press | |
| 291. |
The specific surface of sherical particles is proportional to (where, Dp = diameter of particle). |
| A. | D2p |
| B. | Dp |
| C. | 1/Dp |
| D. | 1/D2p |
| Answer» D. 1/D2p | |
| 292. |
Tube mill compared to ball mill |
| A. | produces finer products. |
| B. | is long in comparison with its diameter. |
| C. | uses smaller balls. |
| D. | all (a), (b) & (c). |
| Answer» E. | |
| 293. |
Sorting classifiers employing differential settling methods for separation of particles make use of the differences in their |
| A. | particle sizes |
| B. | densities |
| C. | terminal velocities |
| D. | none of these |
| Answer» D. none of these | |
| 294. |
Capacity (in tons/hr) of jaw/gyratory crusher is equal to (where, L = length of the receiving opening, cm S = greater width of the discharge opening, cm) |
| A. | 0.01 L.S |
| B. | 0.087 L.S |
| C. | L.S |
| D. | L.S/0.087 |
| Answer» C. L.S | |
| 295. |
Which of the following is not a non-metalliferous mineral? |
| A. | Calcite |
| B. | Fluorspar |
| C. | Quartz |
| D. | Cassiterrite |
| Answer» E. | |
| 296. |
The mechanism of size reduction by a hammer mill is by impact and attrition between the |
| A. | grinding element & the housing. |
| B. | feed particles. |
| C. | both (a) and (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 297. |
Fluid energy mill comes in the category of |
| A. | grinder |
| B. | crusher |
| C. | cutter |
| D. | ultrafine grinder |
| Answer» E. | |
| 298. |
Which of the following is not used as a surface active agent in a flocculation operation? |
| A. | Sodium silicate |
| B. | Quartz |
| C. | Lime |
| D. | Alumina |
| Answer» C. Lime | |
| 299. |
Which is the most suitable conveyor for transportation of sticky material ? |
| A. | Apron conveyor |
| B. | Belt conveyor |
| C. | Screw conveyor |
| D. | Pneumatic conveyor |
| Answer» D. Pneumatic conveyor | |
| 300. |
Temperature of the product during ultrafine grinding |
| A. | increases |
| B. | decreases |
| C. | remains constant |
| D. | may increase or decrease ; depends on the material being ground |
| Answer» B. decreases | |