Free Chemical Process Principles MCQs with Answers

• A. Butyl rubber
• B. Nitrile rubber
• C. Neoprene
• D. Thiokol

Explanation: Buna-N is the copolymer of butadiene and acrylonitrile, so it is called nitrile rubber.

• A. 10 to 103
• B. 107-109
• C. 102-107
• D. 109-1011

Explanation: Polymer molecular masses span a broad range, commonly quoted approximately as 10² to 10⁷, depending on the polymer and measurement basis.

• A. None of these
• B. Acrylonitrile & styrene
• C. Isobutylene & isoprene
• D. Acrylonitrile & butadiene

Explanation: Nitrile rubber is formed by copolymerising acrylonitrile with 1,3-butadiene.

• A. Nylon-66
• B. Polypropylene
• C. PVC
• D. Poly tetra fluoro ethylene

Explanation: Nylon-66 is a copolymer formed by condensation of two different monomers, hexamethylenediamine and adipic acid.

• A. Harder
• B. More flexible
• C. Chemically inert
• D. Tougher

Explanation: LDPE has many branched chains, which prevent close packing and reduce crystallinity.

• A. Polypropylene
• B. Polythene
• C. Polystyrene
• D. PVC

Explanation: Polystyrene is commonly used for disposable hot-drink cups because it is lightweight and a good thermal insulator.

• A. Hydrogen
• B. Covalent
• C. Ionic
• D. None of these

Explanation: Adjacent nylon-66 chains form hydrogen bonds between amide groups, producing strong intermolecular attraction and high strength.

• A. Non-inflammable
• B. Both B. & C.
• C. Stronger
• D. Harder

Explanation: Polypropylene is generally harder and stronger than ordinary polythene because its methyl groups increase chain rigidity and…

• A. Thermosetting
• B. Thermoplastic
• C. Elastometric
• D. Having extremely high softening point

Explanation: Linear polymer chains can slide past one another when heated, so they are normally thermoplastics and can be softened and remoulded.

• A. Fibrous
• B. Rubbery
• C. Leathery
• D. Hard

Explanation: Copolymerising vinyl chloride with vinyl acetate disrupts the rigidity of PVC and produces a softer, flexible material with a leathery…

• A. Polystyrene
• B. Polyvinyl acetate
• C. Polyvinyl chloride-co-vinyl acetate
• D. Polypropylene

Explanation: Polypropylene is manufactured using coordination catalysts such as Ziegler-Natta or metallocene systems, not benzoyl chloride.

• A. Combination of solid & liquid
• B. Liquid
• C. Solid
• D. Neither solid nor liquid

Explanation: Viscoelastic plastics show elastic solid behaviour and viscous liquid-like flow, depending on time, temperature and loading rate.

• A. 50000
• B. 51600
• C. 49200
• D. 50800

Explanation: The PVC repeat unit is C₂H₃Cl, with molecular mass about 62.5. Multiplying 62.5 by the degree of polymerisation, 800, gives approximately…

• A. PVC
• B. Polythene
• C. Teflon/Dacron
• D. Polystyrene

Explanation: Dacron, a polyester, and Teflon, PTFE, are chemically resistant materials used in vascular grafts and can substitute for blood-vessel…

• A. Polychlorophrene
• B. Polyisoprene
• C. Polytetrafluoroethylene
• D. Poly vinyl acetate

Explanation: Neoprene is the trade name for polychloroprene, formed by polymerising chloroprene.

• A. Cellulose acetate
• B. Polyvinyl acetate
• C. Thiokol
• D. PVC

Explanation: Polyvinyl acetate is a soft, waxy, low-molecular-weight polymer used as the gum base in chewing gum.

• A. Addition polymer
• B. Condensation polymer
• C. Polyester
• D. Both B. and C.

Explanation: Dacron is polyethylene terephthalate, a polyester formed by condensation polymerisation of ethylene glycol and terephthalic acid.

• A. All A., B. and C.
• B. Poorer resistance to alkalis
• C. Poorer dyeability
• D. Better heat & acid resistant properties

Explanation: Compared with nylon, Dacron has better resistance to heat and acids but poorer resistance to alkalis and poorer dyeability.

• A. Polyamides
• B. Polyacrylonitrile
• C. Polyolefins
• D. Polyesters

Explanation: Acrylic fibres are based mainly on polyacrylonitrile, whose nitrile groups give the fibre its characteristic properties.

• A. Vinyl acetate
• B. Vinyl chloride
• C. Propylene
• D. Styrene

Explanation: Ziegler-Natta catalysts promote stereospecific coordination polymerisation of olefins such as propylene, producing polypropylene.