Chemical Engineering Basics 1000+ MCQ with answer for RRB ALP

1. The delivery pressure of boiler feed water pump compared to the boiler steam pressure is
A. Same
B. Slightly less
C. Slightly more
D. Much more
Answer : C

2. Faraday's law of electrolysis is related to the
A. Cation speed
B. Atomic number of the cation
C. Equivalent mass of the electrolyte
D. None of these
Answer : C

3. Consideration of the creep is the most important in case of the
A. Blades of gas turbine
B. Piston of an I. C. engine
C. Flywheel of steam engine
D. Cycle chain
Answer : A

4. Unbreakable crockeries are made from __________ polymers.
A. Polystyrene
B. Melamine
C. Polystyrene
D. Polyurethane
Answer : D

5. Pick out the wrong statement.
A. Cold cracking of a weld is due to the presence of hydrogen gas in the weld
B. True stress is given by, ? = ?E (1 + ?E), where ?E and ?E are engineering stress and engineering strain respectively
C. Phosphorous can be easily recovered in the iron blast furnace
D. High residual stress at the surface is beneficial for fatigue properties of a material
Answer : C

6. The kinematic viscosity (in stoke) and the absolute/dynamic viscosity (in poise) are the same for __________ at room temperature.
A. Air
B. Water
C. Mercury
D. Alcohol
Answer : B

7. Force between the molecules of the same substance is called __________ force.
A. Adhesive
B. Cohesive
C. Molecular
D. Vander Walls
Answer : B

8. Frother is added in the froth floatation cell used in ore beneficiation to stabilise the air bubbles (i.e., froth), which will hold the ore particles, but it does not affect the floatability of minerals. Which of the following is not used as a frother?
A. Cresylic acid
B. Xanthaies
C. Pine oil
D. All 'a' 'b' & 'c'
Answer : B

9. In a good rimming steel
A. Carbon and silicon should be low
B. Silicon should be low but carbon should be high
C. Both silicon & carbon should be high
D. Silicon should be high but carbon should be low
Answer : A

10. Cast iron contains __________ percent carbon.
A. 2.5
B. 3.75
C. 4.75
D. 5.25
Answer : A

11. According to thermodynamic Fahrenheit scale, the fundamental interval between ice point to steam point is
A. 180°
B. 212°
C. 32°
D. 273°
Answer : A

12. Material of construction of the electrode used in the electric resistance welding is
A. Stainless steel
B. Graphite
C. Copper
D. Steel
Answer : C

13. Cold cracking in the heat affected zone of a high strength steel weld can take place because of the
A. Retained austenite
B. Martensite formation
C. Relatively high sulphur content in the base metal
D. Sufficient hydrogen present in the welding arc
Answer : B

14. The malleability of a material is the property by virtue of which it can be rolled or hammered into thin sheets. Which of the following materials has the maximum malleability?
A. Lead
B. Copper
C. Aluminium
D. Wrought iron
Answer : A

15. Dies for wire drawing are generally made of
A. Mild steel
B. Stainless steel
C. Carbides
D. High carbon steel
Answer : A

16. The noble metals
A. Are exemplified by Na, K and Li
B. Do not resist corrosion very strongly
C. Are the lowermost in the electro-chemical series of metals
D. None of these
Answer : C

17. Which of the following is preferred for riveting?
A. Lap joint
B. Butt joint
C. Either (A) or (B)
D. Neither (A) nor (B)
Answer : B

18. Difference at any instant between the value of the controlled variable and the set point is called the
A. Deviation
B. Derivative time
C. Error ratio
D. Differential gap
Answer : A

19. A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.
A. 0.01
B. 0.1
C. 0.25
D. 0.5
Answer : B

20. In a neutral solution
A. H⁺ ions are absent
B. OH^- ions are absent
C. Both H⁺ and OH^- ions are present in very small but equal concentration
D. None of these
Answer : C

21. Air-petrol ratio in an automotive petrol engine is around
A. 14 : 1
B. 22 : 1
C. 25 : 1
D. 4 : 1
Answer : A

22. Annealing of white cast iron produces __________ iron.
A. Grey
B. Nodular
C. Malleable
D. Spheroidal
Answer : C

23. Pick out the wrong statement.
A. Weldability of high carbon steel is poorer compared to low carbon steel
B. Invar is a magnetic alloy
C. Magnetic permeability of the diamagnetic material is less than one
D. Martenistic transformation never goes to completion (i.e., 100%) at room temperature
Answer : B

24. Window panes of aeroplanes are normally made of
A. Perspex (PMMA)
B. Teflon (PTFE)
C. Bakelite (phenol formaldehyde)
D. Polystyrene
Answer : A

25. The best guide to judge the general quality of water is the measurement of its
A. pH value
B. Electrical conductivity
C. Turbidity
D. Dissolved oxygen content
Answer : B

26. Which of the following parameters is not responsible for the heat loss from a hot steam carrying bare pipe surface located in a room without fans?
A. Emissivity of pipe surface
B. Diameter & length of the pipe
C. Temperature of hot pipe surface & that of air in the room
D. None of these
Answer : D

27. Screws are specified by their __________ diameters.
A. Minor
B. Major
C. Pitch
D. None of these
Answer : B

28. Maximum heat dissipation occurs from a steel wire (k = 0.5 W/m. k) of 15 mm diameter exposed to air (h = 20W/m² .k), when the insulation thickness is __________ mm.
A. 15
B. 25
C. 10
D. 30
Answer : B

29. The dimensional formula of bulk modulus of elasticity is same as that of the
A. Pressure
B. Density
C. Force
D. None of these
Answer : A

30. Which of the following has the highest modulus of elasticity (about 7 × 10⁶ kg/cm²)?
A. High speed steel
B. Stainless steel
C. Tungsten carbide
D. Superalloys
Answer : C

31. Which of the following terminology is used for the temperature at which new grains are formed in a metal?
A. Eutectic temperature
B. Lower critical temperature
C. Recrystallisation temperature
D. Upper critical temperature
Answer : C

32. The two elements required to form substitutional solid solution should not have
A. Same crystalline structure
B. Same valency
C. Widely differing electronegativity
D. Same atomic sizes
Answer : C

33. Which of the following does not discharge the dust collected as a dry solid?
A. Electrostatic precipitator
B. Wet scrubber
C. Bag filter
D. Gravity settling chamber
Answer : B

34. Pick out the wrong statement.
A. A ferromagnetic material becomes paramagnetic above the 'Curie temperature'
B. Permanent magnets are made of hard materials, whereas electromagnets require soft magnetic materials
C. Soft magnetic materials (e.g., pure iron) have higher permeability and low hysterisis loss and coercive forces
D. Tungsten steel and alnico are not hard magnetic materials
Answer : D

35. The leaching solvent used in Baeyer's process for the purification of bauxite is
A. Ammonium hydroxide
B. Sodium carbonate
C. Sodium hydroxide
D. Ammonium carbonate
Answer : B

36. The amount of different substances produced, when the same quantity of electricity is passed through different solutions are proportional to their
A. Equivalent weight
B. (Equivalent weight)²
C. Molecular weight
D. (Molecular weight)²
Answer : A

37. Which of the following metals reacts violently with water?
A. Mercury
B. Sodium
C. Calcium
D. Magnesium
Answer : B

38. During sensible cooling of air, its wet bulb temperature
A. Decreases but dew point remains constant
B. Increases but dew point remains constant
C. Increases & the dew point decreases
D. Decreases & the dew point increases
Answer : B

39. __________ cannot increase the fatigue strength of a material.
A. Grain refining
B. Grain coarsening
C. Surface hardening
D. Shot peening
Answer : B

40. High endurance limit of carburised machine parts is because of the fact that carburisation
A. Suppresses any stress concentration produced in the parts
B. Enhances the yield point of the material
C. Introduces a compressive layer on the surface
D. Produces a better surface finish
Answer : C

41. The most detrimental impurity in high pressure boiler feed water is
A. Suspended salt
B. Dissolved salt
C. Silica
D. Turbidity
Answer : C

42. __________ stress cannot be sustained by a fluid in equilibrium.
A. Shear
B. Tensile
C. Compressive
D. None of these
Answer : A

43. Which of the following is not an ore of copper?
A. Cryolite
B. Azurite
C. Chalcopyrite
D. Malachite
Answer : A

44. __________ is the process of coating the surface of steel with aluminium oxide, thereby imparting it increased resistance to corrosion & oxidation upto a temperature of 700°C.
A. Veneering
B. Galvanising
C. Electroplating
D. Calorising
Answer : D

45. Maximum consumption of limestone is in the __________ industry.
A. Iron and steel
B. Cement
C. Glass
D. Fertiliser
Answer : D

46. Brazing filler metal used for joining steel plates
A. Melts below the melting points of base metals
B. Melts below 300°C
C. Is copper phosphorous alloy
D. Is copper
Answer : A

47. Regeneration of molecular sieve requires it to be heated to a temperature of about __________ °C.
A. 80-120
B. 200-300
C. 600-800
D. 1000-1100
Answer : D

48. The refractory lining of the bottom in a basic electric arc furnace is made of
A. Silica
B. Alumina
C. Magnesia
D. Fireclay
Answer : C

49. Steel produced from phosphatic iron is __________ in nature.
A. Malleable
B. Ductile
C. Brittle
D. Tough
Answer : C

50. Water hammer is caused in steam carrying pipelines, because of
A. Partial condensation of steam
B. Vibration of the pipeline
C. High degree of superheat of steam
D. Its exposure to torrential rain
Answer : A