Free Chemical Process Principles MCQs with Answers

2,710 Chemical Process Principles MCQs from Chemical Engineering, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

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2,710 questions · page 122 of 136

  • A. Martensite forms in the heat affected zone leading to poor toughness/ductility of the weld
  • B. Excessive ferrite forms in the heat affected zone leading to poor toughness of the weld
  • C. Carbon and other alloying elements get oxidised from the weld pool
  • D. Segregation of carbon and other element occurs in the weld pool leading to poor properties of
  • E. the weld

Explanation: A high carbon equivalent increases hardenability, so rapid cooling of the heat-affected zone can produce hard, brittle martensite.

Correct answer: Martensite forms in the heat affected zone leading to poor toughness/ductility of the weld
  • A. Carbonate
  • B. Sulphate
  • C. Nitrate
  • D. Chloride

Explanation: Ammonium nitrate is mixed with TNT to form amatol, a powerful explosive mixture.

Correct answer: Nitrate
  • A. Compressive
  • B. Tensile
  • C. Toughness
  • D. Hardness

Explanation: The Herbert pendulum determines hardness by observing the damping or loss of swing caused by contact with the material surface.

Correct answer: Hardness
  • A. 0.015
  • B. 0.71
  • C. 1.2
  • D. 3.5

Explanation: Natural water contains about 0.015% deuterium oxide, or heavy water, mainly because a small fraction of hydrogen is naturally present as…

Correct answer: 0.015
  • A. High ambient temperature
  • B. High atmospheric temperature
  • C. Ultraviolet radiation
  • D. Damp atmosphere

Explanation: Ultraviolet radiation supplies enough energy to break polymer bonds and initiate photo-oxidation, causing plastics to become brittle and…

Correct answer: Ultraviolet radiation
  • A. Finer
  • B. Any type of
  • C. Medium
  • D. Coarser

Explanation: Soft materials tend to clog or load a grinding wheel, so larger, coarser grains provide more open space for chip removal and reduce…

Correct answer: Coarser
  • A. nλ = 2d Sin θ
  • B. λ = d Sin 2θ
  • C. λ = 2d Sin 2θ
  • D. nλ = d Sin θ

Explanation: Diffraction from successive crystal planes follows Bragg's law, nλ = 2d sin θ, where d is the interplanar spacing and θ is the glancing…

Correct answer: nλ = 2d Sin θ
  • A. Cylinder
  • B. Runner
  • C. Mold
  • D. None of these

Explanation: In injection moulding, the sprue is the main passage carrying molten material from the nozzle to the runner system.

Correct answer: Runner
  • A. d1/2
  • B. d-1/2
  • C. d
  • D. d-1

Explanation: The Hall-Petch relation states that yield strength increases as grain size decreases: σy = σ0 + k d^-1/2.

Correct answer: d-1/2
  • A. Work hardening
  • B. Creeping effect
  • C. Bauschinger effect
  • D. Stress recovery effect

Explanation: The Bauschinger effect occurs when prior plastic deformation in one direction lowers the yield stress during reverse loading.

Correct answer: Bauschinger effect
  • A. Ductility
  • B. Semi-conductivity
  • C. Yield stress
  • D. Melting point

Explanation: Melting point is primarily determined by the crystal structure and bonding of a material, rather than by ordinary crystal imperfections.

Correct answer: Melting point
  • A. 0.25
  • B. 0.45
  • C. 0.70
  • D. 0.95

Explanation: Alloys generally recrystallise at a higher fraction of their melting temperature than pure metals because solute atoms and other phases…

Correct answer: 0.70
  • A. Densities
  • B. Magnetic permeabilities
  • C. Electrical conductivities
  • D. Hardness

Explanation: Electrostatic separators charge mineral particles and separate them according to how readily they conduct or retain electrical charge.

Correct answer: Electrical conductivities
  • A. Babbitt metal
  • B. Gun metal
  • C. Stainless steel
  • D. Duralumin

Explanation: Duralumin is an aluminium-copper alloy whose strength is increased by solution treatment, quenching and ageing, making it a classic…

Correct answer: Duralumin
  • A. Orange yellow in alkaline medium
  • B. Orange yellow in acidic medium
  • C. Colourless in acidic medium
  • D. Colourless in basic medium

Explanation: Methyl orange is red in acidic solution and changes through orange to yellow as the solution becomes alkaline.

Correct answer: Orange yellow in alkaline medium
  • A. Synthetic
  • B. Parting
  • C. Loam
  • D. Dry

Explanation: Parting sand is dusted over the pattern to prevent the moist green sand from adhering to it during moulding.

Correct answer: Parting
  • A. 100% indirect reduction
  • B. 100% direct reduction
  • C. 50-60% indirect reduction
  • D. 30-40% indirect reduction

Explanation: About 50 to 60% of wustite reduction should occur indirectly by CO, because indirect reduction saves coke and improves blast-furnace…

Correct answer: 50-60% indirect reduction
  • A. 4.4
  • B. 5.6
  • C. 8.4
  • D. 2.4

Explanation: Using pH = -log[H+], pH = -log(4 × 10^-5) = 5 - log 4 = 5 - 0.6 = 4.4. The exponent gives the 5, while log 4 supplies the 0.6 correction.

Correct answer: 4.4
  • A. Stretchability
  • B. Drawability
  • C. Bendability
  • D. None of these

Explanation: The Swift cup test measures drawability by determining how far a sheet can be drawn into a cup before cracking.

Correct answer: Drawability
  • A. High speed steel
  • B. Forged steel
  • C. High carbon steel
  • D. Mild steel

Explanation: Cold chisels require a hard, wear-resistant cutting edge, which is obtained from high-carbon steel after suitable heat treatment.

Correct answer: High carbon steel