All Free Chemical Engineering MCQs with Answers

• A. 5
• B. 70
• C. 500
• D. 1700

Explanation: Seawater contains bromide equivalent to roughly 65 to 70 ppm of bromine.

• A. Explosives
• B. Fertilisers
• C. Aqua regia
• D. Detergents

Explanation: Nitric acid is used in fertilisers, explosives and aqua regia, where it combines with hydrochloric acid.

• A. Cellulose nitrate
• B. Regenerated cellulose
• C. Cellulose acetate
• D. Cellulose acetate butyrate

Explanation: Celluloid is chiefly cellulose nitrate plasticised with substances such as camphor.

• A. Dissolved oxygen
• B. Silica
• C. Suspended salt
• D. Dissolved salt

Explanation: Silica is especially harmful in high-pressure boilers because it forms hard deposits and can be carried with steam to foul turbine blades.

• A. None of these
• B. Flaming
• C. Doctor Zhivago
• D. Alexander

Explanation: Penicillin was discovered by Alexander Fleming in 1928 when he observed that a mould inhibited bacterial growth.

• A. Phenol formaldehyde
• B. Polythene
• C. Poly vinyl chloride
• D. None of these

Explanation: Phenol-formaldehyde is formed by condensation of phenol with formaldehyde, with elimination of water during polymer formation.

• A. Insecticides
• B. Fire retardant
• C. Analgesic drug
• D. Hydrogenation catalyst

Explanation: Chlorine liberates bromine from sodium bromide, and bromine-containing compounds are widely used as flame or fire retardants.

• A. Monosaccharide
• B. Polysaccharide
• C. Disaccharide
• D. None of these

Explanation: Sucrose is formed from one glucose unit and one fructose unit, so it is a disaccharide.

• A. Hardness
• B. Abrasion/resistance
• C. Melting point
• D. None of these

Explanation: Nylon-66 generally has greater hardness, stiffness, abrasion resistance and melting point than Nylon-6; Nylon-6 is noted more for…

• A. (NH4)2SO4
• B. NH4Cl
• C. (NH4)2 NO3
• D. Liquid NH3

Explanation: Ammonia recovered from coke-oven gas is absorbed in sulfuric acid, producing ammonium sulfate: 2NH₃ + H₂SO₄ → (NH₄)₂SO₄.

• A. 10
• B. 25
• C. 50
• D. 98

Explanation: The diaphragm cell produces relatively dilute caustic soda, typically about 10 to 12% NaOH, because the catholyte is diluted by water.

• A. 10
• B. 50
• C. 80
• D. 95

Explanation: Bamboo contains roughly 40 to 50% cellulose, making the approximate value 50% the suitable choice.

• A. Producer gas
• B. Water gas
• C. Coke oven gas
• D. All A., B. and C.

Explanation: CO and H₂ are the defining combustible components of water gas, and both can also occur in producer gas and coke-oven gas.

• A. Both A. and B.
• B. Obtained by treating by-products of the tobacco processing industry
• C. A volatile alkaloid
• D. Neither A. nor B.

Explanation: Nicotine is a volatile alkaloid characteristic of tobacco and is recovered during tobacco processing, including from its by-products.

• A. Continuous
• B. Aerobic batch
• C. Anaerobic batch
• D. None of these

Explanation: Penicillin is produced by aerobic submerged fermentation in batch vessels, because the microorganism requires oxygen and the process is…

• A. Presence of air
• B. Absence of air
• C. High concentration
• D. Presence of ammonium salts

Explanation: Excessively high substrate concentration can inhibit microorganisms through osmotic effects and can also hinder nutrient utilization…

• A. Dehydrated soda ash
• B. Dense soda ash
• C. Sodium bicarbonate
• D. Light soda ash

Explanation: Sodium bicarbonate is calcined in the Solvay process to form sodium carbonate, Na₂CO₃, called light soda ash.

• A. Methyl amine
• B. Naphthalene
• C. Phenol
• D. Xylene

Explanation: Naphthols are hydroxyl derivatives of naphthalene, formed by replacing a hydrogen atom on the naphthalene ring system with an OH group.

• A. Polyisoprene
• B. Neoprene
• C. None of these
• D. Nitrile-butadiene

Explanation: Polyisoprene, neoprene, and nitrile-butadiene rubber are all elastomers because they undergo substantial reversible deformation.

• A. Toluene
• B. Ethyl alcohol
• C. Naphthalene
• D. Benzene

Explanation: In the classical commercial route, benzene is catalytically oxidized to maleic anhydride, commonly using a vanadium oxide catalyst.