Free Chemical Process Principles MCQs with Answers

• A. Forging
• B. Hot rolling
• C. Cold rolling
• D. Casting

Explanation: Cold working such as cold rolling plastically deforms the metal without allowing recovery, leaving residual stresses.

• A. 5
• B. 15
• C. 30
• D. 45

Explanation: Pulverized coal mixes rapidly with air and burns efficiently, so its excess-air requirement is commonly about 15%.

• A. Prevent electrode from contamination
• B. Add alloying elements
• C. Stabilise the arc
• D. Provide protective atmosphere to weld

Explanation: An electrode coating is designed to protect the weld pool from atmospheric contamination, stabilize the arc, and sometimes add alloying…

• A. Abrasion resistance
• B. Toughness
• C. Red hardness
• D. Cutting speed

Explanation: Cutting-tool materials must resist abrasion and retain hardness at high temperature, known as red hardness.

• A. Soft ferrites
• B. High purity iron
• C. Grain oriented Fe-Si alloy
• D. Al-Ni-Co alloy

Explanation: Transformer cores normally use grain-oriented silicon steel because its low hysteresis and eddy-current losses are improved along the…

• A. 87% cementite & 13% Fe
• B. 87% ferrite & 13% C
• C. 93.33% ferrite & 6.67% C
• D. 87% ferrite & 13% cementite

Explanation: Pearlite is the lamellar mixture of ferrite and cementite formed from austenite, containing approximately 87% ferrite and 13% cementite by…

• A. Normalising
• B. Annealing
• C. Tempering
• D. Hardening

Explanation: Spheroidising is a special annealing treatment that changes lamellar cementite into rounded particles, improving machinability and…

• A. CaF2
• B. CaCO3
• C. Ca3(PO4)2
• D. CaCl2

Explanation: The mineral component of bone is commonly represented approximately as tricalcium phosphate, Ca₃(PO₄)₂, although actual bone mineral is…

• A. Ductile
• B. Nodular
• C. Malleable
• D. Grey

Explanation: Malleable iron is made by heat-treating white cast iron for prolonged annealing, which decomposes its cementite and produces temper…

• A. Increases the hydrogen content in the metal
• B. Increases the flame temperature
• C. No significant change occurs
• D. Increases the reducing potential of the gas

Explanation: Steam reacts with hot carbon to form carbon monoxide and hydrogen, and hydrogen acts as an additional reducing gas in the furnace.

• A. Cast iron
• B. Pig iron
• C. Wrought iron
• D. None of these

Explanation: A cupola is a shaft furnace used mainly to melt cast iron, and its tapped product is molten cast iron.

• A. 768
• B. 1127
• C. 1359
• D. 1480

Explanation: Cobalt loses ferromagnetism at its Curie temperature, which is approximately 1120 to 1127 °C.

• A. 1 kg/cm2
• B. 1 bar
• C. 1 kilo Pascal
• D. 1 atmosphere

Explanation: The values are approximately 1 kg/cm² = 0.981 bar, 1 atmosphere = 1.013 bar, and 1 kPa = 0.01 bar.

• A. 2-5
• B. 18-20
• C. 12-15
• D. 6-12

Explanation: In the Hall-Héroult cell, alumina is kept dilute in molten cryolite, typically around 2 to 5 percent, to maintain suitable dissolution and…

• A. Nitrogen oxides
• B. Both A. & B.
• C. Hydrocarbons
• D. Carbon monoxide

Explanation: Photochemical smog forms when nitrogen oxides react with hydrocarbons in sunlight, producing ozone and other oxidants.

• A. Is an electrical insulating material
• B. Of low resistivity is preferred
• C. Should have high thermal conductivity
• D. Need not defy the corrosive action of chemicals

Explanation: A dielectric is a material that does not conduct electric current readily and can sustain an electric field, so it acts as an electrical…

• A. Fats
• B. Carbohydrates
• C. Vitamins
• D. Proteins

Explanation: Most enzymes are proteins whose folded structures provide active sites for catalysis.

• A. Equivalent mass of the electrolyte
• B. Atomic number of the cation
• C. Cation speed
• D. None of these

Explanation: Faraday's second law states that the mass deposited during electrolysis is proportional to the equivalent mass of the substance.

• A. Compression
• B. Tension
• C. Torsion
• D. Shear

Explanation: A cable primarily carries a pulling load, so its suitability is judged by tensile strength.

• A. Less for high melting point metals
• B. Different for different metals
• C. Less for low melting point metals
• D. Almost same for all metals

Explanation: The total volume expansion of many metals from absolute zero to their melting points is empirically found to be approximately similar.