Description : In a cross linked polymer, the monomeric units are linked together to constitute a three dimensional network. Which of the following is a crosslinked polymer? (A) Bakelite (phenol formaldehyde) (B) Polyester (C) Polythene (D) Nylon-6
Last Answer : (A) Bakelite (phenol formaldehyde)
Description : Cross linked polymers formed from bi-and trifunctional groups in which cross-linkage in three dimensions via few chemical bonding across linear chains occur imparts to the polymer __________ properties. (A) Thermoplastic (B) Thermosetting (C) Elastometric (D) Brittleness
Last Answer : (C) Elastometric
Description : Density of low density polythene is about __________ gm/c.c. (A) 0.38 (B) 0.56 (C) 0.81 (D) 0.91
Last Answer : (D) 0.91
Description : . 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 higher (A) Densities (B) Melting point (C) Tensile strength (D) Hardness, rigidity & brittleness
Last Answer : (D) Hardness, rigidity & brittleness
Description : Neoprene is rendered non-inflammable, because of (A) Its cross-linked structure (B) Its linear chain structure (C) The presence of chlorine atoms in its monomer (D) The absence of chlorine atoms in its monomer
Last Answer : (C) The presence of chlorine atoms in its monomer
Description : Pick out the wrong statement. (A) Linear polymers are formed from bifunctional groups only and are normally thermoplastic (B) Cross-linked branched chain polymers are either elastometric or ... (D) Dibasic acids reacts with dihydric alcohols to give polyesters using addition polymerisation reaction
Last Answer : D) Dibasic acids reacts with dihydric alcohols to give polyesters using addition polymerisation reaction
Description : Catalyst used in the production of high density polythene by low pressure Ziegler process is (A) Aluminium triethyl activated with TiCl4 (B) Platinum (C) Molybdenum (D) Nickel
Last Answer : (A) Aluminium triethyl activated with TiCl4
Description : Low density polythene as compared to high density polythene is (A) Harder (B) Tougher (C) Chemically inert (D) More flexible
Last Answer : (D) More flexible
Description : Zeigler process (A) Produces high density polythene (B) Uses no catalyst (C) Produces low density polythene (D) Employs very high pressure
Last Answer : (A) Produces high density polythene
Description : Polythene (low or high density) containers are not corroded by (A) Sulphuric acid (10%) at room temperature (B) Nitric acid (95%) at room temperature (C) Sulphur trioxide at 60°C (D) Any of these
Last Answer : (A) Sulphuric acid (10%) at room temperature
Description : Softening point of high density polythene is about __________ °C. (A) 85 (B) 135 (C) 165 (D) 205
Last Answer : (B) 135
Description : Density of high density polythene is about __________ gm/c.c. (A) 1.18 (B) 1.05 (C) 0.95 (D) 0.99
Last Answer : (C) 0.95
Description : Alloys having more than 80% copper are generally more (A) Abrasion resistant (B) Corrosion resistant (C) Prone to season cracking (D) Machinable
Last Answer : (B) Corrosion resistant
Description : Give one example of each for low density polythene and high density polthene.
Last Answer : Ans: LDP. Squeze bottle and toys HDP. Buckets, dustbin, bottles.
Description : Addition polymerisation is not involved in the manufacture of (A) Low density polythene (B) Poly vinyl chloride (C) Polystyrene (D) Polyhexamethylene adipamide
Last Answer : (D) Polyhexamethylene adipamide
Description : Low pressure Zeigler process of polythene manufacture (A) Employs a pressure of 30 kgf/cm2 (B) Achieves an yield of 95-98% based on ethylene (C) Produces very low density polythene (D) Does not use any catalyst for polymerisation
Last Answer : (B) Achieves an yield of 95-98% based on ethylene
Description : Typical solvent polymerisation reaction conditions for the production of high density polythene by Zeigler process is (A) 7 kgf/cm2 and 70 °C (B) 1000 kgf/cm2 and 100°C (C) 7 kgf/cm2 and 700°C (D) 1 kgf/cm2 (gage) and 70°C
Last Answer : (A) 7 kgf/cm2 and 70 °C
Description : Automobile steering wheels are normally made of (A) Cellulose acetate (B) Cellulose nitrate (C) PVC (D) High density polythene
Last Answer : (A) Cellulose acetate
Description : Transistor parts and refrigerator components are normally made of (A) Polystyrene (B) Polyester (C) High density polythene (D) Polyurethane
Last Answer : (A) Polystyrene
Description : Pick out the wrong statement. (A) Cold cracking of a weld is due to the presence of hydrogen gas in the weld (B) True stress is given by, σ = σE (1 + εE), where σE and εE ... in the iron blast furnace (D) High residual stress at the surface is beneficial for fatigue properties of a material
Last Answer : Option C
Description : The tensile stress in the rim of the flywheel is given by, Where, ρ is mass density and v is linear velocity at the mean radius of the rim. (A) ρv2/2 (B) πρv2 (C) ρv2 (D) 2 ρv2
Last Answer : (C) ρv2
Description : Capacity of field choppers (chaff cutter) is affected by.... (a) Capacity of the feed mechanism (cross-sectional area) (b) Rate of advance of material through throat considered as to be same linear speed of feed mechanism (c) Density of forage material (d) All of the above
Last Answer : (d) All of the above
Description : Capacity of field choppers (chaff cutter) is affected by (a)capacity of the feed mechanism (cross sectional area) (b)Rate of advance of material through throat considered as to be the same linear speed of feed mechanism (c) density of forage material (d) all of the above
Last Answer : (d) all of the above
Description : Crude oil is subjected to vacuum distillation in the last stage, because (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose (B) Lighter/low ... prone to thermal decomposition (C) High purity products can be obtained thereby (D) None of these
Last Answer : (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose
Description : Identify the false statement (A) Martensitic steels are less susceptible to pitting corrosion than austenitic steels (B) Pitting corrosion is usually very localised (C) Hydrogen embrittlement is facilitated by tensile stress (D) Stress corrosion cracking is facilitated by tensile stress
Last Answer : (A) Martensitic steels are less susceptible to pitting corrosion than austenitic steels
Description : Which of the following is an example of stress corrosion? (A) Season cracking of brass (B) Caustic embrittlement of steel (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : What steps can be taken to avoid stress corrosion cracking (SCC) in steel vessels used for storing anhydrous ammonia?
Last Answer : The U.S. National Board of Pressure Vessel Inspectors recommends the following in one of their classic articles: 1. Pressure vessels should be fully stress relieved or fabricated with heads that ... at least 0.2 percent water to inhibit SCC. Source: National Board of Pressure Vessel Inspectors
Description : . A fluid which has a linear relationship between the magnitude of applied shear-stress and the resulting rate of deformation is called a/an __________ fluid. (A) Newtonian (B) Non-Newtonian (C) Ideal (D) Incompressible
Last Answer : (A) Newtonian
Description : Boiling point of a solution according to Duhring's rule is a linear function of the __________ of water. (A) Boiling point (at the same pressure) (B) Viscosity (C) Density (D) Thermal conductivity
Last Answer : (A) Boiling point (at the same pressure)
Description : . Boiling point elevation for a strong and concentrated solution is found by Duhring's rule, which states that at the same pressure, the boiling point of a solution is a linear function of the __________ of pure water. (A) Boiling point (B) Dynamic viscosity (C) Kinematic viscosity (D) Density
Last Answer : (A) Boiling point
Description : Higher boiling fractions like atmospheric residue is distilled under vacuum at low temperature because at high temperature, there is a tendency of the predominance of (A) Thermal cracking (B) Gum formation (C) Coking (D) Discoloration
Last Answer : (C) Coking
Description : In catalytic cracking, the (A) Gasoline obtained has a very low octane number (B) Pressure & temperature is very high (C) Gasoline obtained has very high aromatic content (D) Gasoline obtained has very high amount of gum forming compounds
Last Answer : (C) Gasoline obtained has very high aromatic content
Description : Low pressure Zeigler process for the manufacture of polythene uses a catalyst which is (A) Ni (B) V2O5 (C) Fe (D) Aluminium triethyl combined with titanium tetrachloride
Last Answer : (D) Aluminium triethyl combined with titanium tetrachloride
Description : __________ is a thermosetting plastic. (A) PVC (B) Polythene (C) Bakelite (D) Polystyrene
Last Answer : (C) Bakelite
Description : __________ tubes are good substitute for human blood vessels on heart by-pass operation. (A) PVC (B) Polythene (C) Teflon/Dacron (D) Polystyrene
Last Answer : (C) Teflon/Dacron
Description : Vinyl flooring is done using __________ sheets. (A) Polypropylene (B) PVC (C) Polythene (D) Polyvinyl acetate
Last Answer : (B) PVC
Description : __________ scrap can be recycled & reutilised. (A) Bakelite (B) Epoxy resin (C) Polythene (D) None of these
Last Answer : (C) Polythene
Description : __________ is an addition polymer (A) Nylon (B) Bakelite (C) Polythene (D) None of these
Description : In case of dry spinning of polymers, the polymer solution in a volatile solvent is forced through the spinnerates into a warm air chamber, where the solvent evaporates leaving behind the polymer in the filament ... is used for __________ fibres. (A) Polythene (B) PVC (C) Rayon (D) Polyvinyl acetate
Description : Polythene is a/an __________ polymerisation product. (A) Addition (B) Condensation (C) Thermosetting (D) None of these
Last Answer : (A) Addition
Description : __________ is a thermosetting plastic. (A) Polyvinyl chloride (B) Polythene (C) Bakelite (D) Teflon
Description : __________ is a thermosetting plastic. (A) Polythene (B) Epoxy polymer (C) P.V.C. (D) Polystyrene
Last Answer : (B) Epoxy polymer
Description : __________ is produced using Polycondensation reaction. (A) Polythene (B) Phenol formaldehyde (C) Poly vinyl chloride (D) None of these
Last Answer : (B) Phenol formaldehyde
Description : Thermosetting materials (A) Are cross-linked molecules (B) Soften on application of heat (C) Are solvent soluble (D) None of these
Last Answer : (A) Are cross-linked molecules
Description : 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 of (A) Cross linked polystyrene (B) Phenol formaldehyde resins (C) Polyesters (D) Polyamides
Last Answer : (A) Cross linked polystyrene
Description : Cross linked polymers are (A) Thermoplastic (B) Thermosetting (C) Either (A) or (B) (D) Fibres only
Last Answer : (B) Thermosetting
Description : Close inspection of a failed metal part reveals artifacts on the fracture surface commonly referred to as "striations" or "beach marks". This indicates the component failed as a result of: w) Sudden overloading x) Cyclical loading y) Stress corrosion cracking z) None of the above
Last Answer : ANSWER: X -- CYCLICAL LOADING
Description : Workers working in __________ industry are most prone to white lung cancer. (A) Coal mining (B) Limestone mining (C) Textile (D) Asbestos
Last Answer : (C) Textile
Description : When the nurse auscultates chest sounds that are harsh and cracking, sounding like two pieces of leather being rubbed together, she records her finding as a) pleural friction rub. A ... wheezes are continuous, musical, high-pitched, whistle-like sounds heard during inspiration and expiration.
Last Answer : a) pleural friction rub. A pleural friction rub is heard secondary to inflammation and loss of lubricating pleural fluid.