Free Chemical Process Principles MCQs with Answers

• A. 5
• B. 25
• C. 50
• D. 100

Explanation: Conventional burners can atomise fuel efficiently up to about 25 centistokes, equivalent to roughly 100 Redwood I seconds.

• A. Smoke point
• B. Cetane number
• C. Octane number
• D. Viscosity

Explanation: Aromatic rings resist auto-ignition and therefore give high octane numbers in spark-ignition fuels.

• A. Composition
• B. Viscosity
• C. Optical properties
• D. Specific gravity

Explanation: The Lane and Garton system classifies petroleum mainly using specific gravity, which reflects the relative density of the crude.

• A. All A., B. and C.
• B. Molecular weight
• C. C/H ratio
• D. Boiling points

Explanation: Moving down a crude distillation column gives heavier fractions, so boiling point and molecular weight increase; their carbon-to-hydrogen…

• A. α-methyl naphthalene
• B. 2-2-4 tri methyl pentane
• C. 1, 3 butadiene
• D. Tetra methyl ethylene

Explanation: Iso-octane is 2,2,4-trimethylpentane, a branched C8 hydrocarbon chosen as the high-octane reference fuel and assigned an octane number of…

• A. Viscosity
• B. Smoke point
• C. Ignition delay
• D. Oxidation stability

Explanation: Cetane number indicates diesel ignition quality: a higher value means a shorter ignition delay after fuel injection.

• A. 2
• B. 5
• C. 10
• D. 25

Explanation: Crude oil can contain substantial associated or entrained water when produced, with water content reaching about 25 percent in some well…

• A. More than 100
• B. Round about 100
• C. Between 50 and 100
• D. Less than 25

Explanation: Tetraethyl lead has an antiknock effectiveness corresponding to an octane number above the 100 reference value of iso-octane, so a small…

• A. Equal weight of diesel & the aniline are completely miscible
• B. Equal volume of aniline & the test sample are completely miscible
• C. Equal weight of aniline & the test sample are completely miscible
• D. Aniline vaporises

Explanation: The aniline point is the lowest temperature at which equal volumes of aniline and the petroleum sample become completely miscible.

• A. Low molecular weight & low boiling point compounds present in petroleum
• B. Desirable in catalytic cracking feedstock, because they produce coke
• C. Readily oxidisable and form carbonaceous sludge
• D. All A., B. & C.

Explanation: Asphalts are heavy, high-boiling petroleum residues that can oxidise and form carbonaceous sludge.

• A. Fluctuation of ambient temperature during day and night
• B. Presence of unsaturated air
• C. Both A. and B.
• D. Neither A. nor B.

Explanation: Breathing loss results from expansion and contraction of vapour in a storage tank as ambient temperature changes, especially between day…

• A. Acid
• B. Solvent extraction
• C. Alkali
• D. Clay

Explanation: Solvent extraction removes low-viscosity-index aromatic components from lubricating oil, thereby producing an appreciable improvement in…

• A. Emulsification tendency
• B. Water content
• C. Water separation characteristics
• D. Water absorbing capacity from atmosphere

Explanation: WSIM indicates how effectively a petroleum fuel separates from water after mixing, so it measures water-separation characteristics.

• A. Wax
• B. Water
• C. Organic impurities
• D. Sulphur & its compounds

Explanation: Sweetening treats sour petroleum products by removing or converting objectionable sulphur compounds, especially hydrogen sulphide and…

• A. 35
• B. 70
• C. 105
• D. 150

Explanation: High-speed diesel commonly has an aniline point near 70 °C, although the exact value varies with its composition.

• A. Modern theory
• B. Carbide theory
• C. Engler theory
• D. All A., B. and C.

Explanation: The inorganic carbide theory does not adequately account for the nitrogen- and sulphur-containing compounds found in crude oil.

• A. 60
• B. 70
• C. 80
• D. 90

Explanation: Catalytic reforming converts low-octane naphtha components into aromatics and branched hydrocarbons, raising the octane number of…

• A. Straight run gasoline
• B. Catalytically cracked gasoline
• C. Catalytically reformed gasoline
• D. Polymer gasoline

Explanation: Straight-run gasoline comes directly from crude distillation and contains fewer high-octane branched and aromatic components than…

• A. Viscosity
• B. Viscosity index
• C. Aniline point
• D. Flash point

Explanation: A multigrade oil maintains suitable viscosity over a broad temperature range, which requires a high viscosity index.

• A. Vacuum gas oil
• B. Reduced crude
• C. Naphtha or straight run gasoline
• D. Atmospheric gas oil

Explanation: The usual reformer feed is naphtha, often the straight-run naphtha fraction from crude distillation.