All Free Chemical Engineering MCQs with Answers
Every Chemical Engineering question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
6,983 questions · page 124 of 350
- A. Specific surface ratio
- B. Shape factor
- C. Sauter diameter
- D. Surface area per unit mass
Explanation: Sphericity compares the surface area of a volume-equivalent sphere with the actual particle surface area, so its reciprocal is a shape…
Correct answer: Shape factor- A. Capacity and effectiveness of the screen is increased
- B. Screening becomes progressively easier
- C. Screening becomes progressively more difficult
- D. None of these
Explanation: Very small particles are difficult to screen because they tend to agglomerate, pass slowly through the apertures, and blind the screen.
Correct answer: Screening becomes progressively more difficult- A. Jaw crusher
- B. Gyratory crusher
- C. Cone crusher
- D. Roll crusher
Explanation: Roll crushers generally operate with a relatively small size-reduction ratio, commonly about 3 to 4, whereas jaw, cone, and gyratory…
Correct answer: Roll crusher- A. Surface area per unit mass
- B. Screen size
- C. Micron
- D. Centimetre
Explanation: Ultrafine particles are too small for convenient measurement by ordinary screens, centimetres, or even practical screen-size descriptions.
Correct answer: Surface area per unit mass- A. State or manner of application of the crushing force
- B. All A., B. and C.
- C. Elastic constant of the material
- D. Ultimate strength of the material
Explanation: The Rittinger number is not a universal constant; it depends on the material properties and on how the crushing force is applied.
Correct answer: All A., B. and C.2466. During filtration operation, the filtrate encounters the resistance of the ___________________?
- A. Filter medium
- B. All A., B. and C.
- C. Channel carrying the slurry to the upstream side of the cake and filtrate away from the filter
- D. medium
- E. Cake
Explanation: Filtrate flow is opposed by resistance from the filter medium, the deposited cake, and the connected flow passages carrying slurry and…
Correct answer: All A., B. and C.- A. Pug mill
- B. Pan mixer
- C. Banbury mixer
- D. Charge can mixer
Explanation: A Banbury mixer is an intensive internal mixer designed for compounding rubber and plastic materials, using strong shear and kneading…
Correct answer: Banbury mixer- A. With minimum possible small balls
- B. At a speed more than the critical speed
- C. At a speed equal to the critical speed
- D. At a speed less than the critical speed
Explanation: Above the critical speed, centrifugal force holds the balls against the mill wall and prevents effective impact and cascading.
Correct answer: At a speed less than the critical speed- A. Poor grindability
- B. Easier grindability
- C. High power consumption in grinding
- D. None of these
Explanation: Rittinger's number measures new surface produced per unit energy, so a larger value means more surface is obtained for the same energy and…
Correct answer: Easier grindability- A. Hammer crusher
- B. Roll crusher
- C. Ball mill
- D. Gyratory crusher
Explanation: Carbon black requires fine pulverisation, for which a ball mill is suitable because repeated impact and attrition reduce the material to…
Correct answer: Ball mill- A. Sand bed filter
- B. Plate and frame filter press
- C. Batch basket centrifuge
- D. Vacuum filter
Explanation: A vacuum filter is suitable because it can be constructed with corrosion-resistant filter materials and handles abrasive solids without…
Correct answer: Vacuum filter- A. Independent of ΔP
- B. ∝ 1/ ΔP
- C. ∝ √ΔP
- D. ∝ ΔP
Explanation: For an incompressible cake, the cake structure does not change as pressure rises, so its specific resistance remains constant and is…
Correct answer: Independent of ΔP- A. Cake thickness
- B. Characteristics of the feed slurry
- C. Both A. & B.
- D. Neither A. nor B.
Explanation: Rotary drum vacuum-filter capacity depends on cake thickness, which controls the filtration resistance, and on feed-slurry characteristics…
Correct answer: Both A. & B.- A. to the square root of the volume to surface ratio of the product
- 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
- D. Calls for relatively less energy for the smaller product particles, than does the Rittinger law
- E. States that the work required for the crushing is proportional to the new surface created
Explanation: Compared with Rittinger's law, Bond's law predicts relatively less energy for producing very small particles because its energy…
Correct answer: Calls for relatively less energy for the smaller product particles, than does the Rittinger law- A. 6.V/D.S
- B. V/6D.S
- C. D.S/V
- D. V/D.S
Explanation: Sphericity is the surface area of a sphere having the same volume divided by the actual particle surface area.
Correct answer: 6.V/D.S- A. Compressible cakes and laminar
- B. Incompressible cake and laminar
- C. Compressible cake and turbulent
- D. Incompressible cake and turbulent
Explanation: For laminar filtration through an incompressible cake, resistance increases linearly with cake thickness and hence with filtrate volume…
Correct answer: Incompressible cake and laminar- A. 1.0
- B. 0.5
- C. 1.34
- D. 4.34
Explanation: Dry grinding generally requires more energy than wet grinding because liquid reduces agglomeration and improves transport of particles.
Correct answer: 1.34- A. Apron conveyor
- B. Belt conveyor
- C. Bucket elevator
- D. Screw conveyor
Explanation: A screw conveyor can move cohesive, semi-solid, and pasty materials because its rotating screw positively pushes the material forward.
Correct answer: Screw conveyor- A. 0.5 Wi
- B. 1.34 Wi
- C. Wi
- D. 3.34 Wi
Explanation: Open-circuit grinding generally consumes more energy than closed-circuit grinding because particles are not repeatedly returned for…
Correct answer: 1.34 Wi- A. Titanium oxide
- B. Calcium oxide
- C. Cobalt oxide
- D. Manganese oxide
Explanation: Hematite is mainly Fe2O3 and may contain common gangue or impurity oxides such as TiO2, CaO, and MnO.
Correct answer: Cobalt oxide