All Free Chemical Engineering MCQs with Answers

• A. Large number of slip systems
• B. Low stacking fault energy
• C. Coarse grain size
• D. High work hardening rate

Explanation: Cross-slip requires a dislocation to move from one slip plane to another, which is hindered when the stacking-fault energy is low.

• A. Compression ignition engine
• B. Diesel engine
• C. Engine having carburettor
• D. Both B. & C.

Explanation: A spark plug ignites the air-fuel mixture in a spark-ignition engine, which commonly has a carburettor.

• A. Neither A nor B
• B. Manganese
• C. Both A nor B
• D. Carbon

Explanation: Carbon raises the ductile-to-brittle transition temperature of steel by promoting harder, more brittle microstructures.

• A. Copper
• B. Lead
• C. Wrought iron
• D. Aluminium

Explanation: Malleability is the ability to undergo plastic deformation under compression, and lead is exceptionally malleable among these choices.

• A. Tensile strength
• B. Compressive strength
• C. Thermal co-efficient of expansion
• D. Young's modulus

Explanation: Steel and concrete have nearly equal coefficients of thermal expansion, so temperature changes produce similar dimensional changes in…

• A. Haemoglobin
• B. None of these
• C. Hypo solution
• D. Chlorophyll

Explanation: Magnesium is the central metal ion in the chlorophyll molecule, where it plays a key role in absorbing light for photosynthesis.

• A. Hydrogen
• B. Deuterium
• C. Neon
• D. Helium

Explanation: Ordinary hydrogen-1, called protium, has one proton and no neutron; deuterium has one neutron and helium and neon contain neutrons in…

• A. High speed steel
• B. Carbide
• C. Cast alloy
• D. Plain carbon steel

Explanation: Carbide tools retain hardness at much higher temperatures than high-speed steel, allowing greater cutting speeds.

• A. Silver
• B. Aluminium
• C. Carbon
• D. Stainless steel

Explanation: Carbon has much lower electrical conductivity than metals such as silver and aluminium; stainless steel is also relatively resistive but…

• A. All amorphous
• B. Ceramic
• C. All crystalline
• D. Non-crystalline organic polymeric

Explanation: Viscoelasticity is especially characteristic of non-crystalline organic polymers, which show both elastic recovery and time-dependent…

• A. Lime & Magnesia
• B. Alkali oxide
• C. Alumina
• D. None of these

Explanation: Lime and magnesia are useful basic fluxing constituents in iron ore and can improve its metallurgical value.

• A. Glass
• B. Diamond
• C. Brine
• D. Kerosene

Explanation: Diamond has a refractive index of about 2.42, higher than ordinary glass, brine, and kerosene.

• A. Both silicon & carbon should be high
• B. Silicon should be low but carbon should be high
• C. Carbon and silicon should be low
• D. Silicon should be high but carbon should be low

Explanation: Rimming steel requires low carbon and silicon so that carbon monoxide evolution produces the characteristic rim during solidification.

• A. Pure oxygen has been used for combustion
• B. Nitrogen percentage in the fuel is very high
• C. Hydrogen is not present in the fuel
• D. Excess air has been used for combustion

Explanation: The oxygen remaining after combustion, together with nitrogen from air, indicates that more air than the theoretical requirement was…

• A. (Molecular weight)2
• B. (Equivalent weight)2
• C. Molecular weight
• D. Equivalent weight

Explanation: Faraday's law states that the mass deposited or liberated by a fixed quantity of electricity is proportional to the substance's equivalent…

• A. Hot metal
• B. Flue gases
• C. Slag
• D. Refractory lining

Explanation: Phosphorus is readily reduced and dissolves in the molten iron, so most of it reports to the hot metal in the blast furnace.

• A. 8.82
• B. 9.81
• C. 10.88
• D. 0.95

Explanation: The balance reading gives weight in kilogram-force: 1.8 kgf = 2g/9.81 kgf. Hence g = 1.8(9.81)/2 = 8.83 m/s², approximately 8.82 m/s².

• A. Refine coarse grain structure obtained during hot working
• B. Improve mechanical properties
• C. Improve yield strength
• D. Improve ductility

Explanation: Normalising refines the grain structure and generally raises strength, including yield strength, while improving overall mechanical…

• A. Zn
• B. Cu
• C. Fe
• D. Ni

Explanation: Insulin contains zinc, which is coordinated by specific histidine residues and helps stabilize the insulin structure.

• A. 80-85
• B. 60-65
• C. 40-45
• D. 20-25

Explanation: Indian iron ore commonly contains about 60–65% iron, although the exact grade varies by deposit.