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 307 of 350
- A. Decreases its tensile strength
- B. Increases its ductility
- C. Decreases its ductility
- D. Does not affect its ductility
Explanation: Plastic deformation during work hardening increases dislocation density, making further deformation more difficult and raising tensile…
Correct answer: Decreases its ductility- A. Cobalt
- B. None of these
- C. Nickel
- D. Zinc
Explanation: Zinc is a non-ferromagnetic metal, whereas cobalt and nickel are ferromagnetic. Therefore zinc is the non-magnetic choice.
Correct answer: Zinc- A. Austenitic
- B. Ferritic
- C. Martensitic
- D. None of these
Explanation: 18/8 stainless steel contains approximately 18% chromium and 8% nickel.
Correct answer: Austenitic- A. Brittleness
- B. Ductility
- C. Toughness
- D. Malleability
Explanation: Percentage elongation measures how much a specimen stretches plastically before fracture, so it is a standard measure of ductility.
Correct answer: Ductility- A. Dilute HCI
- B. Concentrated H2SO4
- C. Acetic acid
- D. None of these
Explanation: Acetic acid attacks lead and can form soluble or weakly protective lead compounds, allowing corrosion to continue.
Correct answer: Acetic acid- A. Suppresses the decomposition of Fe3C
- B. Reduces its fluidity
- C. Increases the contraction of the metal
- D. Increases the formation of graphite
Explanation: Silicon promotes graphitisation in cast iron by encouraging decomposition of cementite, Fe₃C, into iron and graphite.
Correct answer: Increases the formation of graphite- A. Harden the surface
- B. Prevent the action of water
- C. Increase its glossiness and lustre
- D. Prevent the action of oxygen
Explanation: Galvanising coats iron with zinc, isolating it from moisture and forming a sacrificial protective layer.
Correct answer: Prevent the action of water- A. Eutectic
- B. Upper critical
- C. Recrystallisation
- D. Lower critical
Explanation: Recrystallisation is the formation of new, strain-free grains when a cold-worked metal is heated sufficiently.
Correct answer: Recrystallisation- A. Alumel
- B. Constantan
- C. Chromel
- D. Invar
Explanation: Invar is an iron-nickel alloy containing about 36% nickel and is used where extremely low thermal expansion is required.
Correct answer: Invar- A. Steel
- B. Cast iron
- C. Brass
- D. Gun metal
Explanation: Concentrated caustic soda is commonly stored in steel drums because carbon steel has satisfactory resistance under ordinary storage…
Correct answer: Steel- A. Cobalt
- B. Nickel
- C. Tungsten
- D. Chromium
Explanation: Cobalt increases the coercivity and residual magnetism of steel, making cobalt steels suitable for permanent magnets.
Correct answer: Cobalt- A. Stainless steel
- B. Cast iron
- C. Mild steel
- D. Monel
Explanation: Sugar-cane mills use heavy cast-iron rolls because cast iron withstands the large compressive loads and provides a durable, wear-resistant…
Correct answer: Cast iron- A. Moving mercury and graphite
- B. Moving mercury and carbon
- C. Graphite and moving mercury
- D. Moving mercury and crimped steel wire
Explanation: In a mercury cell, graphite or another suitable inert material serves as the anode, while flowing mercury is the cathode.
Correct answer: Graphite and moving mercury- A. Protected from rusting
- B. Harder
- C. Alumina coated iron
- D. None of these
Explanation: Galvanised iron has a zinc coating that separates the iron from the atmosphere and also provides sacrificial protection if the coating is…
Correct answer: Protected from rusting- A. Parkerising
- B. Sherardizing
- C. Anodising
- D. None of these
Explanation: Sherardising is a zinc diffusion coating process in which zinc powder diffuses into the surface of iron or steel during heating.
Correct answer: Sherardizing- A. Abrasive
- B. Reinforced
- C. Refractory
- D. Fully metallic
Explanation: Cermets combine a ceramic phase with a metallic phase and retain the hardness and high-temperature resistance associated with refractory…
Correct answer: Refractory- A. Glass lined steel
- B. Nickel clad steel
- C. Lead lined steel
- D. Aluminium
Explanation: Molten phthalic anhydride is commonly stored in aluminium vessels because aluminium offers suitable resistance to the molten product.
Correct answer: Aluminium- A. Tungsten, chromium and vanadium
- B. Tungsten, vanadium and chromium
- C. Vanadium, chromium and tungsten
- D. Chromium, tungsten and vanadium
Explanation: The designation 18-4-1 for high-speed steel refers to approximately 18% tungsten, 4% chromium and 1% vanadium.
Correct answer: Tungsten, chromium and vanadium- A. Non-ferrous metals
- B. Low carbon steels
- C. Non-metals
- D. Stainless steel
Explanation: Low-carbon steel sheets are commonly galvanised because zinc protects the exposed steel both as a barrier and through sacrificial action.
Correct answer: Low carbon steels- A. Monel metal
- B. Babbitt metal
- C. German silver
- D. Dow metal
Explanation: Dow metal is a magnesium-based alloy, usually containing aluminium and other additions, so it has low density and is classified as a light…
Correct answer: Dow metal