Free Chemical Process Principles MCQs with Answers

• A. Oxidation of Na+ ions
• B. Reduction of Cl- ions
• C. Reduction of Na+ ions
• D. Oxidation of Cl- ions

Explanation: At the anode, chloride ions lose electrons and are oxidised to chlorine gas: 2Cl− → Cl2 + 2e−.

• A. Protein
• B. Biological catalyst
• C. Amino acid
• D. Enzyme

Explanation: Haemoglobin is a conjugated protein containing iron, which enables it to bind and transport oxygen in blood.

• A. -83
• B. -183
• C. -196
• D. -218

Explanation: Liquid oxygen boils at about −183°C at atmospheric pressure. Nitrogen boils at −196°C, so that value is the common distractor in…

• A. Water hating
• B. Soil loving
• C. Water loving
• D. None of these

Explanation: Hydrophilic means water-loving, so this part of a soap or detergent molecule interacts readily with water.

• A. Preferred over contact process for producing 98 to 100% H2SO4 and various oleums
• B. Non-catalytic and operates only on pyrites
• C. A batch process for directly producing high strength (98 to 100%) H2SO4
• D. None of these

Explanation: The chamber process produces relatively dilute sulphuric acid, generally around 60 to 70%, rather than 98 to 100% acid or oleum.

• A. Soda ash
• B. Limestone
• C. Coke
• D. Sodium sulphate

Explanation: Sodium silicate is produced by fusing silica in sand with sodium carbonate, commonly called soda ash, at high temperature.

• A. Manufacture of cationic detergent
• B. Drilling of petroleum wells and pickling of steel sheets
• C. Treatment of spent fuel of nuclear reactor
• D. None of these

Explanation: Hydrochloric acid is widely used to acidize petroleum wells and to pickle steel, where it removes mineral scale and rust.

• A. Making protective gas (95% N2 + 5% H2) for annealing of cold rolled steel strip coils
• B. Fire fighting purposes
• C. Both A. & B.
• D. Neither A. nor (B)

Explanation: Nitrogen is used as an inert protective atmosphere, including the 95% nitrogen and 5% hydrogen mixture for annealing steel coils.

• A. 0.5
• B. 5
• C. 20
• D. 35

Explanation: Spent lye from soap manufacture contains dissolved glycerine along with alkali salts and other impurities, with glycerine commonly around…

• A. Gravity separation
• B. Electromagnetic separation mainly
• C. Froth floatation
• D. Roasting

Explanation: Hematite ore is commonly concentrated by gravity separation because the iron-bearing mineral has a higher density than much of its gangue.

• A. Bleaching powder
• B. Alum
• C. Calcium sulphate
• D. Chlorine

Explanation: Alum, usually hydrated aluminium sulfate, hydrolyses in water to form a gelatinous precipitate that traps suspended particles and helps…

• A. Bleaching
• B. Digestion
• C. Depithing
• D. None of these

Explanation: Bagasse contains pith, the soft cellular material surrounding the fibres, so it must first undergo depithing before pulping.

• A. PVC
• B. Silicone
• C. Polyamides
• D. Polyurethanes

Explanation: Flexible mattress foam is commonly produced by reacting polyols with diisocyanates to form polyurethane foam.

• A. Remove lignin by way of crystallisation
• B. Avoid mechanical weakening of fibre
• C. Increase the cellulose content
• D. None of these

Explanation: Injecting cold black liquor cools the heavily digested chips and limits excessive exposure to high temperature and alkali, which can…

• A. Ca(OH)2
• B. CO2
• C. C2H2
• D. CaCO3

Explanation: Calcium carbide hydrolyses according to CaC₂ + 2H₂O → C₂H₂ + Ca(OH)₂. Acetylene is the principal desired product, while calcium hydroxide…

• A. 3
• B. 12
• C. 22
• D. 0.3

Explanation: High-temperature carbonisation of coal is designed mainly to produce coke, and the associated tar yield is relatively small, typically…

• A. Soap from lye
• B. Glycerine from lye
• C. The metallic soap
• D. The unsaponified fat from soap

Explanation: Salt increases the density of the aqueous lye and decreases soap solubility, causing the soap to separate and float as a distinct layer.

• A. 18-23
• B. 2-8
• C. 27-32
• D. 1-4

Explanation: Ordinary beer commonly contains about 2–8% alcohol by volume, depending on the style and fermentation.

• A. Fatty acid
• B. Fatty alcohols
• C. Tallow
• D. Detergents

Explanation: Tallow is a common animal fat used as the fatty raw material in soap manufacture; it reacts with alkali during saponification.

• A. Bacterial growth
• B. None of these
• C. Turbidity
• D. Taste and odour

Explanation: Activated carbon adsorbs many dissolved organic compounds responsible for unpleasant taste and odour in water.