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 150 of 350
- A. Injection
- B. Calendaring
- C. Extrusion
- D. Blow moulding
Explanation: Blow moulding forms hollow plastic articles by inflating a heated tube or parison against the walls of a mould.
Correct answer: Blow moulding- A. Brasses
- B. High carbon steels
- C. Thermosetting polymers
- D. Borosilicate glasses
Explanation: Season cracking is stress-corrosion cracking traditionally associated with brass, especially when residual tensile stress and ammonia or…
Correct answer: Brasses- A. √T
- B. √y
- C. 1/√P
- D. 1/√ρ
Explanation: The sound speed is proportional to √(γP/ρ), or, for an ideal gas, to √T.
Correct answer: 1/√P- A. Visco-elastic
- B. Isotropic
- C. Elastic
- D. Plastic
Explanation: Working above or below the recrystallisation temperature involves permanent shape change once the applied stress exceeds the yield…
Correct answer: Plastic- A. Fusion
- B. Forge
- C. Resistance
- D. Arc
Explanation: Thermit welding uses the intense heat of an exothermic chemical reaction to melt the joint metal and filler, producing coalescence by…
Correct answer: Fusion- A. Silicon
- B. Manganese
- C. Nickel
- D. Chromium
Explanation: The work-hardening steel used in excavator buckets and bulldozer blades is manganese steel, commonly containing iron, carbon, and a high…
Correct answer: Manganese- A. Polymerisation
- B. Oxidation
- C. Photochemical reaction
- D. None of these
Explanation: Photosynthesis uses light energy to drive the conversion of atmospheric carbon dioxide and water into carbohydrates, so it is a…
Correct answer: Photochemical reaction- A. Rebound
- B. Indentation
- C. Dynamic
- D. Scratch
Explanation: Mohs hardness measures scratch resistance by seeing which standard mineral can scratch another.
Correct answer: Scratch- A. Both B. & C.
- B. Tin
- C. Lead
- D. Aluminium
Explanation: Aluminium is extracted electrolytically from alumina by the Hall-Héroult process.
Correct answer: Both B. & C.- A. Minor
- B. Pitch
- C. Major
- D. None of these
Explanation: A screw's major diameter is the largest diameter measured over the crests of its thread and is used for its nominal specification.
Correct answer: Major- A. Pig
- B. Carbon free
- C. Wrought
- D. Cast
Explanation: A cupola melts pig iron and scrap to produce cast iron for foundry moulds.
Correct answer: Cast- A. Excess of
- B. Lack of free
- C. Decrease in
- D. None of these
Explanation: Heating breaks covalent bonds in the semiconductor lattice, creating additional electron-hole pairs and therefore an excess of free charge…
Correct answer: Excess of- A. Phosphate coating is used as an excellent base for paints & enamels
- B. Phosphate coating is less corrosion resistant than chromate coating
- C. The base metal to be electroplated is normally made the cathode of the electrolytic cell and
- D. Calorising is the process of coating steel with chromium
- E. coating metal is made the anode
Explanation: Calorising means coating steel or another metal with aluminium to improve oxidation resistance, not coating it with chromium.
Correct answer: Calorising is the process of coating steel with chromium- A. States that stress is inversely proportional to strain upto elastic limit
- B. Applies beyond limit of proportionality in stress-strain curve
- C. Applies to elastic deformation
- D. None of these
Explanation: Hooke's law states that stress is proportional to strain within the proportional limit, which lies in the elastic region.
Correct answer: Applies to elastic deformation2995. 'GASOHOL' widely used in Brazil as a motor fuel is a mixture of alcohol and____________________?
- A. Light hydrocarbon gases (e.g. butane or propane)
- B. LPG
- C. Petrol
- D. None of these
Explanation: Gasohol is gasoline blended with alcohol, usually ethanol. It is therefore a petrol-alcohol fuel, not an LPG or light-gas mixture.
Correct answer: Petrol- A. Occurs higher in the electro-chemical series of metals
- B. Is exemplified by magnesium plate
- C. Is much cheaper than the cathodic base material to be guarded against corrosion
- D. All A, B. & C.
Explanation: A sacrificial anode must be more readily oxidized than the protected pipeline, such as magnesium, and is usually inexpensive relative to…
Correct answer: All A, B. & C.- A. Achieve very high purity of aluminium (99.9%)
- B. Both B. & C.
- C. Electrolytically dissociate alumina
- D. Keep the electrolyte in liquid condition by the generation of heat
Explanation: In the Hall-Héroult cell, electric current electrolytically decomposes dissolved alumina and the electrical resistance of the molten bath…
Correct answer: Both B. & C.- A. FeO
- B. MgO
- C. SiO2
- D. MnO2
Explanation: Ganister is a naturally occurring siliceous refractory material, so it contains predominantly silica, SiO₂.
Correct answer: SiO2- A. 4
- B. 6
- C. 8
- D. 12
Explanation: In a simple cubic lattice, each atom touches four neighbors in its own plane, plus one directly above and one below.
Correct answer: 6- A. 9.5 : 1
- B. 12.5 : 1
- C. 15.5 : 1
- D. 18.5 : 1
Explanation: Methane requires 2 mol of oxygen per mole: CH₄ + 2O₂ → CO₂ + 2H₂O. Since air contains about 4.76 mol of air per mole of oxygen, the…
Correct answer: 9.5 : 1