All Free Chemical Engineering MCQs with Answers

• A. Smoke
• B. Carbon monoxide
• C. Oxygen
• D. Temperature

Explanation: Incomplete combustion leaves part of the carbon-containing fuel only partially oxidised, producing carbon monoxide instead of carbon…

• A. Young
• B. Mature
• C. Neither A nor B
• D. Both A & B

Explanation: Very young coals such as lignite and very mature coals such as anthracite generally lack the plastic properties needed for coke formation.

• A. None of these
• B. Incomplete combustion
• C. Smoky flame
• D. Increased fuel consumption

Explanation: Excess air dilutes the flame and carries additional nitrogen and unused oxygen through the stack, increasing stack heat loss.

• A. Hardness & strength
• B. Porosity
• C. Bulk density
• D. Reactivity

Explanation: The Micum tests measure the mechanical performance of coke during tumbling, including resistance to breakage and abrasion.

• A. Hydrogen
• B. Acetylene
• C. Carbon monoxide
• D. Methane

Explanation: Acetylene burns over an especially broad concentration range in air, approximately 2.5% to 81% by volume.

• A. Must contain moderate quantities of ash, moisture, sulphur and volatile matters
• B. Should be brittle
• C. Should have high porosity
• D. Should have low fusion point of its ash

Explanation: Metallurgical coke needs substantial porosity so that gases can pass through the furnace burden and reactions can occur effectively.

• A. Carbon monoxide
• B. Oxygen
• C. Hydrogen
• D. Hydrocarbons

Explanation: Luminosity in a fuel flame comes mainly from incandescent carbon particles formed by cracking heavy hydrocarbons.

• A. CO (upto 65%) & CO2
• B. CO2 & H2
• C. CO & O2
• D. CO2 & O2

Explanation: LD converter gas is formed when oxygen removes carbon from molten iron, producing a gas rich in CO, commonly up to about 65%, with some…

• A. Produce weak coke
• B. Produce strong coke
• C. Both B. and C.
• D. May damage the coke oven walls during carbonisation

Explanation: Highly caking coal softens and swells strongly during carbonisation, which helps produce strong coke but can exert excessive pressure on…

• A. Unburnt gases
• B. Luminous
• C. Yellow
• D. Non-luminous

Explanation: The outer non-luminous zone has sufficient oxygen for nearly complete combustion, so it reaches the highest temperature.

• A. 200 °F
• B. 200 °C
• C. 200 °K
• D. 200 °R

Explanation: The designation C.T.F.-200 refers to a target preheating temperature of about 200°F for this pitch-creosote fuel before atomisation.

• A. H2
• B. CO
• C. C2H2
• D. C2H6

Explanation: Gross and net calorific values differ mainly because GCV includes the heat recovered when product water vapour condenses.

• A. Cracking
• B. Reforming
• C. Partial oxidation
• D. Gasification

Explanation: Partial oxidation releases heat because part of the fuel is oxidised completely or substantially to CO2 and H2O.

• A. Sapropelic coals
• B. Liptobiolites
• C. Humic coals
• D. None of these

Explanation: Cannel and boghead coals are rich in algal and resinous organic matter and are grouped as sapropelic coals.

• A. CO2
• B. CH4
• C. H2
• D. CO

Explanation: Anaerobic digestion of cattle dung produces biogas, whose principal combustible constituent is methane, usually accompanied by substantial…

• A. 5
• B. 21
• C. 40
• D. 48

Explanation: A caking index near 21 indicates adequate plasticity and bonding ability for a metallurgical coke blend.

• A. 2.5
• B. 7.5
• C. 10.5
• D. 14.5

Explanation: Unscientific coal storage can cause losses through wind removal of fine particles, typically around 2.5% of the stored coal.

• A. Kerosene
• B. Diesel
• C. Fuel oil
• D. Gasoline

Explanation: Laboratory gas is traditionally produced by cracking kerosene, yielding a gaseous fuel mixture suitable for laboratory use.

• A. Ensure its complete combustion
• B. Facilitate easy ash removal
• C. Enhance its calorific value
• D. Provide trouble free operation

Explanation: Pulverising coal increases its surface area, allowing better contact with air and making combustion more nearly complete.

• A. Give less yield of tar and gas on carbonisation
• B. Burn with a small non-smoky flame
• C. None of these
• D. Have a very high calorific value

Explanation: High-volatile coal produces greater quantities of tar and gas during carbonisation and generally burns with a long, smoky flame.