⚗️ Chemical Engineering Solved MCQs with Answers

Practice 1920 approved ⚗️ Chemical Engineering questions with verified answers from the 🛠️ Engineering Essentials subject for Pakistan exams.

1920 solved MCQs

Which of the following natural bio polymers are formed as a result of polymerisation of amino-acids ?Answer: Proteins Nylon-66 is manufactured fromAnswer: Adipic acid and hexamenthylene diamine. Thermosplastic materialsAnswer: None of these Polyvinyl acetate is never used for makingAnswer: Moulded articles Typical solvent polymerisation reaction conditions for the production of high density polythene by Zeigler process isAnswer: 7 kgf/cm² and 70 °C. Vulcanisation of rubber does not increase itsAnswer: Softness In nylon-6, the number 6 represents the total number ofAnswer: Carbon atoms in the linear polymer chain. Cellulose content in bomboo fibre is about __________ percent.Answer: 50 In step growth polymerisation, generally only one type of reaction & some basic mechanism is involved. Step growth polymerisation reaction is not involved in the manufacture ofAnswer: Cross linked polystyrene. Which of the following has the weakest intermolecular forces ?Answer: Polyisoprene Properties of a polymer is affected by theAnswer: All (a), (b). In condensation polymerisation as compared to addition polymerisationAnswer: The monomers contain two functional groups. In a linear polymer, the monomeric units are linked together to form long straight chains. The cross linked or branched chain polymers compared to linear polymers have higherAnswer: Hardness, rigidity & brittleness Which of the following is a copolymer ?Answer: SBR Styrene butadiene rubber (SBR) is never used for makingAnswer: Front wheel tyres of aeroplanes (i.e., heavy duty tyres) Cross linked polymers areAnswer: Thermosetting Pick out the wrong statement.Answer: Teflon is formed by step growth polymerisation. Which of the following rubbers has the widest service temperature range (-75 to 275°C) ?Answer: Silicone rubber Nylon-66 compared to nylon-6 hasAnswer: Higher hardness. Scouring is a finishing operation during the manufacture of fibre, which aims at __________ of fibres.Answer: Detergent solution washing Synthetic rubberAnswer: Is highly permeable to air & water and is readily attacked by chemicals & atmospheric gases. Melamine formaldehyde resin which has a very high anti tacking properties, is not used for theAnswer: Strengthening of plaster of paris. In a co-polymer, the repeating units contain two different monomers. Which of the following is a copolymer ?Answer: Buna-S Cation exchange resins used in water treatment is made from __________ resin.Answer: Urea formaldehyde Size range of polymer molecules varies from __________ metre.Answer: 10⁻² to 10⁻⁵ Which of the following is generally not drawn into fibre ?Answer: Unsaturated polyesters Condensation polymerization of caprolac-tum is carried out in the reactor maintained at a temperature of __________ °C for producing nylon-6.Answer: 250-280 Which of the following is not a natural polymer ?Answer: Polyurethane In case of wet spinning of polymers, the polymer solution is forced through spinnerates into, a coagulating bath to give a filament form. Wet spinning is not used in case of the __________ fibres.Answer: Saturated polyester Melt spinning of polymers involves the forcing of polymer melt through spinnerettes (fine holes) into an atmosphere kept at a temperature lower than the melting point of the polymer, which causes the fine diameter polymer melt to harden into filaments. Melt spinning is not used in case of the __________ fibres.Answer: Acrylic