Free Chemical Process Principles MCQs with Answers

2,710 Chemical Process Principles MCQs from Chemical Engineering, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

Last updated

2,710 questions · page 51 of 136

  • A. Lignite
  • B. Bituminous
  • C. Semi-anthracite
  • D. Anthracite

Explanation: Coal maturity increases from lignite through bituminous and semi-anthracite to anthracite.

Correct answer: Anthracite
  • A. All A., B. and C.
  • B. Sulphur content is lower
  • C. Flue gas has lower dew point thereby facilitating more waste heat recovery
  • D. Emissivity factor is higher

Explanation: PCM generally has higher flame emissivity, lower sulphur content, and produces flue gas with a lower acid dew point than furnace oil.

Correct answer: All A., B. and C.
  • 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…

Correct answer: Carbon monoxide
  • 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.

Correct answer: Both A & B
  • 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.

Correct answer: Increased fuel consumption
  • 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.

Correct answer: Hardness & strength
  • 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.

Correct answer: Acetylene
  • 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.

Correct answer: Should have high porosity
  • 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.

Correct answer: 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…

Correct answer: CO (upto 65%) & CO2
  • 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…

Correct answer: Both B. and C.
  • 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.

Correct answer: Non-luminous
  • 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.

Correct answer: 200 °F
  • 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.

Correct answer: CO
  • 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.

Correct answer: Partial oxidation
  • 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.

Correct answer: 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…

Correct answer: CH4
  • 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.

Correct answer: 21
  • 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.

Correct answer: 2.5
  • 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.

Correct answer: Kerosene