Free Chemical Process Principles MCQs with Answers

• A. Teflon
• B. Bakelite
• C. SBR
• D. None of these

Explanation: Teflon is polytetrafluoroethylene, formed by addition polymerisation of only tetrafluoroethylene.

• A. Low temperature thermal insulation as in refrigerator and air conditioners
• B. Acoustic control and ceiling for building
• C. High temperature thermal insulation in furnaces
• D. Packing of delicate electronic gadgets

Explanation: Expanded polystyrene softens and decomposes at elevated temperatures, so it is unsuitable for furnace insulation.

• A. Alumina
• B. Bromine
• C. Platinum
• D. Sulphur

Explanation: Sulphur is the most common vulcanising agent for rubber because it forms cross-links between polymer chains, improving strength…

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

Explanation: Polypropylene is commonly used for bag liners because it is tough, chemically resistant and has low moisture absorption.

• A. Nylon
• B. Bakelite
• C. Polythene
• D. None of these

Explanation: Polythene is polyethylene, produced by addition polymerisation in which ethene molecules join without eliminating a small molecule.

• A. Polystyrene
• B. Phenol formaldehyde
• C. Urea formaldehyde
• D. Thiokol

Explanation: Thiokol is a polysulfide rubber, so it behaves as an elastomer and can undergo large reversible deformation.

• A. Extrusion
• B. Transfer
• C. Injection
• D. Compression

Explanation: Extrusion continuously forces softened plastic through a die, producing constant-cross-section products such as tubes and pipes.

• A. Vulcanise it
• B. Protect it from deterioration on exposure to air
• C. Make it non-inflammable
• D. Make it thermosetting

Explanation: Diphenylamine acts as an antioxidant by reacting with oxidation products and free radicals, thereby slowing deterioration of rubber in…

• A. -20
• B. 50
• C. 250
• D. 500

Explanation: PVC emulsion polymerisation is commonly conducted near 50°C, where the initiator and emulsion system provide a practical polymerisation…

• A. Injection
• B. Green sand
• C. Shell
• D. Dry sand

Explanation: Injection moulding melts plastic and forces it into a closed mould, making it suitable for producing large numbers of shaped plastic…

• A. Ni
• B. Aluminium triethyl combined with titanium tetrachloride
• C. Fe
• D. V2O5

Explanation: The Ziegler catalyst system combines an organoaluminium compound, commonly aluminium triethyl, with titanium tetrachloride.

• A. 50
• B. 75
• C. 90
• D. 99

Explanation: Ring-opening polymerisation of caprolactam to nylon-6 is equilibrium-limited, so industrial conversion is about 90%, with some monomer and…

• A. Water impermeable cellophane
• B. Teflon
• C. Cellulose acetate
• D. Polythene

Explanation: Polythene films can stretch to roughly 100% elongation because the flexible polymer chains uncoil and orient under tension.

• A. All A., B. and C.
• B. Amorphous glassy state
• C. Partially crystalline state
• D. Melts & rubber like state

Explanation: Depending on chain structure, temperature and processing, polymers may occur as melts or rubber-like materials, amorphous glassy solids…

• A. Polyamide
• B. Polyester
• C. Polyolefin
• D. Addition polymer

Explanation: Alkyd resins form when polyols react with polybasic acids, producing polyester chains, often modified with fatty acids or oils.

• A. Nylon-6
• B. PVC
• C. Polystyrene
• D. Nylon-66

Explanation: Nylon-66 has good toughness, abrasion resistance and dimensional stability, making it suitable for toothbrush bristles.

• A. 100
• B. 150
• C. 350
• D. 450

Explanation: A commonly quoted general service-temperature limit for many plastics is about 150°C, although the exact limit depends strongly on the…

• A. Polystyrene
• B. poly-methyl-methacrylate
• C. Unsaturated polyester
• D. Polypropylene

Explanation: Perspex is the trade name for polymethyl methacrylate, abbreviated PMMA.

• A. Thiokol
• B. Dacron
• C. Plexiglass or Lucite
• D. Teflon

Explanation: PMMA is widely marketed as Plexiglass or Lucite because it is a clear, rigid acrylic resin.

• A. Plasticiser
• B. Paint & varnish
• C. Film forming materials
• D. Fibers

Explanation: Alkyd resins are widely used in paints, varnishes, plasticisers and film-forming coatings.