All Free Chemical Engineering MCQs with Answers

• A. Remove double bonds
• B. None of these
• C. Improve its resistance to oxidation
• D. Raise its melting point

Explanation: Hydrogenation removes carbon-carbon double bonds, raises the melting point, and improves resistance to oxidation by reducing unsaturation.

• A. Yeast
• B. Maltase
• C. Diastase
• D. None of these

Explanation: Diastase, mainly the amylase enzyme, hydrolyses starch into maltose and related smaller sugars.

• A. Tackiness
• B. Resistance to the action of organic solvent
• C. Maximum service temperature
• D. Tensile strength

Explanation: Vulcanisation forms sulphur cross-links between rubber chains, reducing their stickiness or tackiness.

• A. Saponification
• B. Esterification
• C. Neutralisation
• D. Acidification

Explanation: An alcohol reacts with a carboxylic acid to form an ester and water, a reaction known as esterification.

• A. As a plasticiser for unsaturated polyester
• B. As an anti-skinning agent in paint
• C. In the manufacture of synthetic rubber
• D. None of these

Explanation: Butadiene's principal industrial application is polymerisation to synthetic rubbers such as polybutadiene and styrene-butadiene rubber.

• A. Lead glass
• B. High silica (borosilicate) glass
• C. Fibre glass
• D. Photo-sensitive glass

Explanation: Photosensitive glass changes its structure or optical properties when exposed to light and is used in specialised optical applications.

• A. Palmitic
• B. Oxalic
• C. Stearic
• D. Oleic

Explanation: Oleic acid is unsaturated because it contains a carbon-carbon double bond.

• A. Blotting paper
• B. Writing paper
• C. Bond paper
• D. Coloured paper

Explanation: Blotting paper is designed to absorb liquids, so fillers that improve opacity or smoothness are avoided because they would reduce…

• A. Sugar
• B. Paper
• C. Alcohol from molasses
• D. Phenol formaldehyde

Explanation: A Fourdrinier machine forms a continuous sheet of paper from a dilute pulp suspension on a moving wire screen, followed by pressing and…

• A. All A , B. and C.
• B. It contains ≥ 40% metal
• C. The metal present in it is costly
• D. A metal can be economically extracted from it

Explanation: An ore is a mineral or rock from which a metal can be extracted economically using available processing methods.

• A. Soda ash
• B. Washing soda
• C. Plaster of Paris
• D. Calcite

Explanation: Anhydrous sodium carbonate, Na₂CO₃, is called soda ash. Washing soda is hydrated sodium carbonate, commonly Na₂CO₃·10H₂O, so the water of…

• A. Cement
• B. Caustic soda
• C. Potteries
• D. Glass

Explanation: Brine, a concentrated aqueous solution of sodium chloride, is electrolysed to produce caustic soda along with chlorine and hydrogen.

• A. Extractive distillation technique
• B. Liquid extraction technique
• C. Evaporation followed by vacuum distillation
• D. None of these

Explanation: Lye from soap manufacture is first concentrated by evaporation, then glycerine is separated by vacuum distillation.

• A. Penicillin
• B. Streptomycin
• C. Tetracycline
• D. Quinine

Explanation: Quinine is an antimalarial alkaloid, not an antibiotic. Penicillin, streptomycin and tetracycline are all established antibacterial…

• A. Biochemical
• B. Chemical
• C. Photochemical
• D. Electrochemical

Explanation: Enzymes are biological organic catalysts that accelerate biochemical reactions, often under mild temperature and pH conditions.

• A. Impart adhesive properties
• B. Improve opacity
• C. Impart resistance to penetration by liquids
• D. None of these

Explanation: Rosin soap is used for sizing paper, making the fibres less readily wetted and therefore more resistant to penetration by water and other…

• A. Caustic soda
• B. Soda lime
• C. Caustic potash
• D. Soda ash

Explanation: The Solvay process converts brine and limestone into sodium carbonate, commonly called soda ash.

• A. 30
• B. 50
• C. 70
• D. 90

Explanation: Commercial benzol is a light-oil fraction containing roughly 70% benzene, with the remainder mainly toluene, xylenes and other…

• A. Detergent
• B. Soap
• C. Oil hydrogenation
• D. Paint

Explanation: Soap manufacture by saponification of fats or oils produces glycerine along with soap.

• A. Calcium perchlorate
• B. Soda lime
• C. Slaked lime
• D. None of these

Explanation: Bleaching powder is made by passing chlorine over dry slaked lime, Ca(OH)2, producing calcium hypochlorite-containing material.