chemical engineering MCQs – Page 118

Practise multiple-choice questions from chemical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

chemical engineering Mcqs
2341. Toothed roll crushers achieve size reduction by___________________?
comments icon0

A. Tearing (shear) and compression

B. Impact and attrition

C. Both A. & B.

D. Neither A. nor B.

2342. Energy consumed for crushing one ton of material ranges from ______________ kWh?
comments icon0

A. 4 to 5

B. 0.01 to 0.1

C. 2 to 3.5

D. 0.5 to 1.5
2343. As per Taggarts formula, the capacity (kg/hr) of Jaw & Gyratory crushers (for gapes of 10 to 60 cms) is equal to (where, L = Length of feed opening, cms S = Maximum width of discharge opening, cms) ?
comments icon0

A. ?(LS)

B. LS

C. 250 LS

D. 93 LS
2344. Which of the following is not used as a surface active agent in a flocculation operation ?
comments icon0

A. Lime

B. Quartz

C. Sodium silicate

D. Alumina

2345. Moore filter is a ______________ filter ?
comments icon0

A. Sand

B. Leaf

C. Rotary

D. Press

2346. A propeller agitator_______________?
comments icon0

A. Runs at very slow speed (2 rpm)

B. All A., B. and C.

C. Is used for mixing high viscosity pastes

D. Produces mainly axial flow
2347. In filtration, the use of filter aid helps in__________________?
comments icon0

A. Enhancing the cake porosity in case of a dense impermeable cake

B. Accelerating the rate of filtration

C. Deplugging the filter medium

D. Reducing the filtration pressure

2348. About 2-3 hp, power per gallon of a thin liquid provides vigorous agitation in an agitator. Power number in agitation is given by __________________?
comments icon0

A. P. gc. ?/?2

B. P. gc/n2. D2. ?

C. P. gc/n3. D2. ?

D. n3. D3. ?/P. gc

2349. Wheat is ground into flour in a___________________?
comments icon0

A. Fluid energy mill

B. Hammer crusher

C. Roller crusher

D. Impact mill

2350. The assumption made in Elis method in distillation is that enthalpy concentration lines of vapor and liquid are __________________?
comments icon0

A. Parallel

B. Straight

C. Both parallel and straight

D. Neither parallel nor straight

2351. Critical speed of rotation, N (in rps rotation per second) of a trammel is equal to (where, g = acceleration due to gravity = 9.81 m/sec2 and, r = radius of trammel, metre.) ?
comments icon0

A. 2?. ?(g/r)

B. (1/?). ?(g/r)

C. (1/2?). ?(g/r)

D. ?(g/r)

2352. In an interphase mass transfer process, the lesser the solubility of a given solute in a liquid, the higher are the chances that the transfer process will be_________________?
comments icon0
A. Gas phase resistance controlled

B. Driven by a non-linear driving force

C. Liquid phase resistance-controlled

D. Impossible

2353. Sphericity of raschig ring (whose length and diameter are equal) is___________________?
comments icon0

A. > 1

B. 2

C. 1

D. < 1

2354. During washing of filter at the end of constant pressure filtration, the rate of washing equals the rate of filtration___________________?
comments icon0

A. At time zero

B. At the end of filtration, but decreases with time subsequently

C. When half the filtrate has been obtained

D. At the end of filtration
2355. Which of the following oxides is not present in hematite iron ore ?
comments icon0

A. Calcium oxide

B. Titanium oxide

C. Cobalt oxide

D. Manganese oxide

2356. The Knudsen diffusivity is dependent on the ______________________?
comments icon0

A. Molecular velocity only

B. Molecular mean free path only

C. Molecular velocity and pore radius of the catalyst

D. Pore radius of the catalyst only

2357. In case of grinding in a ball mill__________________?
comments icon0
A. All A., B. and C

B. Its capacity decreases with increasing fineness of the products

C. Wet grinding achieves a finer product size than dry grinding

D. Grinding cost and power requirement increases with increasing fineness of the products

2358. In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the__________________?
comments icon0

A. Concentration

B. None of these

C. Temperature and pressure

D. Nature of the constituents

2359. ______________ mill is not a revolving mill ?
comments icon0
A. Cage

B. Tube

C. Pebble

D. Compartment

2360. In a size reduction crushing operation, feed size is 100 to 300 mm. while the product size is 10 to 50 mm. This is a case of the _____________ crushing?
comments icon0

A. Primary

B. Secondary

C. Ultrafine

D. Fine