Free Chemical Process Principles MCQs with Answers
2,710 Chemical Process Principles MCQs from Chemical Engineering, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
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- A. PVC
- B. Nylon
- C. Polystyrene
- D. None of these
Explanation: PVC tends to dehydrochlorinate and decompose on heating before it reaches a useful melting state.
Correct answer: PVC- A. Bakelite
- B. Perspex
- C. Teflon
- D. PVC
Explanation: Teflon, or PTFE, has very low surface energy and excellent chemical and thermal resistance, so food does not readily stick to its coating.
Correct answer: Teflon- A. Sebacic acid
- B. Terephthalic acid
- C. Benzoic acid
- D. Adipic acid
Explanation: Nylon-66 is formed from hexamethylenediamine and adipic acid, so adipic acid is its dicarboxylic organic acid monomer.
Correct answer: Adipic acid- A. Ion-exchange resins
- B. Fountain pen barrels
- C. Formica table tops
- D. Combs
Explanation: Ion-exchange resins require sulphonated phenol-formaldehyde resin, whereas non-sulphonated hard bakelite is used for items such as combs…
Correct answer: Ion-exchange resins- A. 1.18
- B. 1.05
- C. 0.95
- D. 0.99
Explanation: HDPE has a density close to 0.95 g/cm³ because its relatively linear chains pack efficiently.
Correct answer: 0.95- A. Addition polymer
- B. Elastomer
- C. Thermoplastic
- D. None of these
Explanation: Bakelite is a phenol-formaldehyde condensation polymer with a cross-linked thermosetting structure.
Correct answer: None of these- A. 1-1000
- B. 1000-1500
- C. 1500-2000
- D. 2000-2500
Explanation: Natural rubber can stretch to roughly 700 to 1,000 percent of its original length, giving it exceptional flexibility among elastomers.
Correct answer: 1-1000- A. Hydrofluoric acid
- B. Sulphuric acid
- C. Organic peroxides
- D. None of these
Explanation: Organic peroxides such as benzoyl peroxide decompose readily to form free radicals, which initiate addition polymerisation.
Correct answer: Organic peroxides- A. Hexamethylene diamine and the ring
- B. None of these
- C. Adipic acid and the ring
- D. Hexamethylene diamine and the adipic acid
Explanation: The two sixes in nylon-6,6 indicate six carbon atoms in each monomer: hexamethylene diamine and adipic acid.
Correct answer: Hexamethylene diamine and the adipic acid- A. The presence of chlorine atoms in its monomer
- B. Its linear chain structure
- C. Its cross-linked structure
- D. The absence of chlorine atoms in its monomer
Explanation: Neoprene contains chlorine atoms because it is made from chloroprene, and chlorine increases resistance to ignition and burning.
Correct answer: The presence of chlorine atoms in its monomer- A. Are formed by addition polymerisation
- B. Have linear structure
- C. Have three dimensional structure
- D. None of these
Explanation: Thermosetting polymers develop extensive cross-linking during curing, producing a rigid three-dimensional network.
Correct answer: Have three dimensional structure- A. For surface coating of automobiles & air crafts
- B. For film forming materials
- C. As plasticiser for PVC & nitrocellulose
- D. For fibre making
Explanation: Glyptal and other alkyd resins are used in coatings, films and sometimes as plasticisers, but they are not normally used for making…
Correct answer: For fibre making- A. A copolymer
- B. A condensation polymer
- C. Obtained by polymerising vinyl cyanide
- D. All A., B. and C.
Explanation: Orlon, apparently misspelled here as Orion, is an acrylic fibre made by polymerising vinyl cyanide, or acrylonitrile.
Correct answer: Obtained by polymerising vinyl cyanide- A. - 20°C and 1 kgf/cm2
- B. 5°C and 1 kgf/cm2
- C. 0°C and 1 kgf/cm2
- D. 0°C and 3 kgf/cm2
Explanation: Cold SBR is made by low-temperature emulsion polymerisation, commonly maintained near 5°C with a pressure of about 1 kgf/cm².
Correct answer: 5°C and 1 kgf/cm2- A. Phosphorous
- B. Rosin
- C. Pine oil
- D. Carbon black
Explanation: Carbon black reinforces rubber by increasing toughness, strength, abrasion resistance and wearing quality.
Correct answer: Carbon black- A. Tackiness
- B. Resistance to organic solvents
- C. Tensile strength
- D. Working temperature range
Explanation: Vulcanisation forms sulphur cross-links between rubber chains, reducing chain slippage and surface stickiness.
Correct answer: Tackiness- A. Polymer termination step
- B. Initial hydrolysis of silicone monomer
- C. Condensation of siloxane to silicone
- D. None of these
Explanation: In silicone-rubber manufacture, the initial hydrolysis of the silicone monomer is treated as the rate-controlling step.
Correct answer: Initial hydrolysis of silicone monomer- A. Hardeners
- B. Anti-shrinkage agents
- C. Transparency improver
- D. Plasticisers
Explanation: Phosphate esters such as tricresyl phosphate and triphenyl phosphate act as plasticisers by lowering the effective rigidity of polymer…
Correct answer: Plasticisers- A. In a chain without the elimination of water
- B. With the elimination of small amount of water
- C. Of the same monomer by elimination of small molecules of water
- D. None of these
Explanation: A copolymer contains two or more different monomer species joined in the polymer chain, as in an addition polymerisation without loss of…
Correct answer: In a chain without the elimination of water- A. Unsaturated polyester
- B. Alkyd resins
- C. Saturated polyester
- D. Amino resins
Explanation: Alkyd resins are formed by reacting a polybasic acid or anhydride such as phthalic anhydride with a polyhydric alcohol such as glycerol.
Correct answer: Alkyd resins