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All 90 questions with answers

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  1. 1.
    Who is known as the "Father of Modern Polymer Science"?
    Show answer and explanation
    Answer: B —
    Hermann Staudinger
    Hermann Staudinger is widely recognized as the father of polymer science for his pioneering work on macromolecules.
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  2. 2.
    Monomers used in addition polymerization is
    Show answer and explanation
    Answer: B —
    Unsaturated compounds
    Addition polymerization typically involves monomers with unsaturated bonds, such as double or triple bonds.
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  3. 3.
    Polyester fibre are prepared by
    Show answer and explanation
    Answer: A —
    Melt spinning
    Polyester fibers like polyethylene terephthalate are commercially prepared using melt spinning.
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  4. 4.
    Functionality of Adipic acid is
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    Answer: B —
    Two
    Adipic acid is a dicarboxylic acid containing two carboxyl groups, hence its functionality is two.
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  5. 5.
    Which polymer is used in bullet-proof vests?
    Show answer and explanation
    Answer: D —
    Kevlar
    Kevlar is a high-strength aramid fiber widely used in the manufacture of bullet-proof vests.
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  6. 6.
    Which of the following polymers can be synthesized by ring opening polymerization?
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    Answer: A —
    Nylon 6
    Nylon 6 is synthesized by the ring-opening polymerization of caprolactam.
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  7. 7.
    Which protein plays a role in the latex coagulation mechanism by bridging between rubber particles?
    Show answer and explanation
    Answer: B —
    Hevein
    Hevein is a protein found in natural rubber latex that plays a significant role in coagulation.
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  8. 8.
    Identify the component which has the maximum composition in the Hevea rubber latex?
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    Answer: D —
    Water
    Water is the continuous phase and has the maximum composition (around 55-65%) in Hevea rubber latex.
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  9. 9.
    In the production of PLC, yellow pigments can be destroyed by
    Show answer and explanation
    Answer: C —
    Fractional coagulation
    Fractional coagulation is used in the production of pale latex crepe (PLC) to remove yellow pigments.
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  10. 10.
    The concentration of Ammonia used for preserving field latex is
    Show answer and explanation
    Answer: D —
    1% by weight on latex
    High ammonia preserved field latex typically uses about 1% ammonia by weight on latex.
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  11. 11.
    Which among the tapping system is adopted one or two years before replanting or replacing crop?
    Show answer and explanation
    Answer: B —
    Slaughter tapping
    Slaughter tapping is an intensive tapping system adopted just before a rubber tree is cut down for replanting.
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  12. 12.
    Natural rubber latex can be coagulated using
    Show answer and explanation
    Answer: B —
    Formic acid
    Acids such as formic acid or acetic acid are commonly used to coagulate natural rubber latex.
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  13. 13.
    Glass transition temperature of Natural Rubber is
    Show answer and explanation
    Answer: C —
    –70°C
    The glass transition temperature (TgT_g) of natural rubber is approximately −70∘C-70^\circ\text{C}.
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  14. 14.
    Surgical gloves are manufactured by
    Show answer and explanation
    Answer: A —
    Dipping
    Surgical gloves are manufactured using the dipping process in compounded latex.
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  15. 15.
    Parthenium Argentatum is commonly known as
    Show answer and explanation
    Answer: A —
    Gauyule rubber
    Parthenium argentatum is the scientific name for the guayule shrub, which produces natural rubber.
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  16. 16.
    Electro decantation is related with
    Show answer and explanation
    Answer: D —
    Concentration of latex
    Electro-decantation is a method used for concentrating natural rubber latex using an electric field.
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  17. 17.
    Linear low density polyethylene is a copolymer of ethylene and a small fraction of _______.
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    Answer: A —
    Butene
    Linear low-density polyethylene (LLDPE) is a copolymer of ethylene with small amounts of alpha-olefins such as 1-butene, 1-hexene, or 1-octene.
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  18. 18.
    In Lassaigne's test for the detection of halogens, the sodium fusion extract is first boiled with concentrated nitric acid. This is performed to
    Show answer and explanation
    Answer: C —
    Decompose and
    Boiling with concentrated nitric acid decomposes cyanide and sulfide ions if present, which would otherwise interfere with the test.
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  19. 19.
    Which of the following fibre is known as "Dacron"?
    Show answer and explanation
    Answer: A —
    Polyester
    Dacron is a well-known brand name for polyester fiber (polyethylene terephthalate).
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  20. 20.
    Resole is an example for
    Show answer and explanation
    Answer: B —
    Thermosetting polymer
    Resole is a type of phenolic resin, which is a thermosetting polymer.
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  21. 21.
    Which of the following is a thermoplastic polymer?
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    Answer: A —
    PVC
    Polyvinyl chloride (PVC) is a widely used thermoplastic polymer.
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  22. 22.
    The catalyst used in the polymerization of propylene is
    Show answer and explanation
    Answer: B —
    Ziegler-Natta catalysts are typically used for the polymerization of propylene.
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  23. 23.
    The term "Tenacity" is associated with
    Show answer and explanation
    Answer: D —
    Fibre
    Tenacity is a measure of the strength of a fiber or yarn.
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  24. 24.
    Which of the following grade of polystyrene is well suited for the purpose of insulating applications?
    Show answer and explanation
    Answer: A —
    Expandable
    Expandable polystyrene (EPS) is widely used for thermal insulation.
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  25. 25.
    An example for dienes used in the manufacture of EPDM is
    Show answer and explanation
    Answer: D —
    All the above mentioned
    EPDM (Ethylene Propylene Diene Monomer) uses various dienes like ENB, DCPD, and VNB as the third monomer.
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  26. 26.
    Identify the monomers of butyl rubber.
    Show answer and explanation
    Answer: A —
    Isoprene and Isobutylene
    Butyl rubber is a copolymer of isobutylene with a small amount of isoprene.
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  27. 27.
    Which is an inorganic polymer?
    Show answer and explanation
    Answer: C —
    Silicone rubber
    Silicone rubber is an inorganic polymer based on a silicon-oxygen backbone.
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  28. 28.
    Chloroprene rubber is vulcanized using
    Show answer and explanation
    Answer: A —
    Metal oxide
    Chloroprene rubber (Neoprene) is typically vulcanized using metal oxides like zinc oxide and magnesium oxide.
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  29. 29.
    The synthetic rubber used in the inner tubes of tyre is
    Show answer and explanation
    Answer: C —
    IIR
    IIR (Butyl rubber) is used for inner tubes due to its excellent air impermeability.
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  30. 30.
    Higher acrylonitrile content in NBR leads to
    Show answer and explanation
    Answer: D —
    All the above mentioned
    Increasing the acrylonitrile content in NBR improves oil resistance, hardness, and tensile strength.
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  31. 31.
    An example for a homopolymer is
    Show answer and explanation
    Answer: A —
    Polybutadiene rubber
    Polybutadiene is a homopolymer made from butadiene monomers.
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  32. 32.
    Buna N is a copolymer of ______ and ______.
    Show answer and explanation
    Answer: B —
    Acrylonitrile and Butadiene
    Buna N is another name for Nitrile Rubber, which is a copolymer of acrylonitrile and butadiene.
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  33. 33.
    Ribbed Smoked sheets are graded according to the standards as per
    Show answer and explanation
    Answer: B —
    IS 15361 : 2003
    IS 15361:2003 is the Indian Standard for grading Ribbed Smoked Sheets.
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  34. 34.
    DIN Abrader is used to measure
    Show answer and explanation
    Answer: C —
    Abrasion resistance
    The DIN abrader is a standard instrument used to measure the abrasion resistance of rubber.
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  35. 35.
    ASTM D412 standard defines procedures used to evaluate _______ properties of vulcanized thermoset rubber and thermoplastic elastomers.
    Show answer and explanation
    Answer: B —
    Tensile
    ASTM D412 specifies standard test methods for evaluating tensile properties of vulcanized rubber and thermoplastic elastomers.
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  36. 36.
    ______ indicates the resistance of raw rubber to deterioration during processing or aging.
    Show answer and explanation
    Answer: B —
    PRI
    Plasticity Retention Index (PRI) measures the resistance of raw rubber to thermal oxidation and deterioration.
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  37. 37.
    Hardness is measured using
    Show answer and explanation
    Answer: A —
    Durometer
    A durometer is commonly used to measure the indentation hardness of rubber and plastics.
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  38. 38.
    In tensile testing, the standard rate of grip separation in rubbers is
    Show answer and explanation
    Answer: C —
    500±50500 \pm 50 mm/min
    Standard testing standards specify a grip separation rate of 500±50500 \pm 50 mm/min for rubber tensile testing.
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  39. 39.
    The percentage of dirt in ISNR 5 is
    Show answer and explanation
    Answer: A —
    0.05%
    The maximum permissible dirt content (by mass) in Indian Standard Natural Rubber grade ISNR 5 is 0.05%.
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  40. 40.
    Which among the following parameter is considered for grading ISNR?
    Show answer and explanation
    Answer: A —
    Dirt Content
    Dirt content, ash content, volatile matter, nitrogen, and initial plasticity are key parameters considered for grading ISNR.
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  41. 41.
    As per ASTM D395 for the determination of compression set under constant force in air, a force of _______ is applied to the specimen for a set time at a set temperature.
    Show answer and explanation
    Answer: A —
    1.8 kN
    ASTM D395 Method B specifies a constant force application of 1.8 kN.
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  42. 42.
    ISNR grade which doesn't show storage hardness
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    Answer: D —
    ISNR-3 CV
    Constant Viscosity (CV) grades like ISNR-3 CV are treated with hydroxylamine to prevent storage hardening.
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  43. 43.
    Higher VFA number in a natural rubber latex indicates
    Show answer and explanation
    Answer: A —
    Loss of colloidal stability
    Volatile Fatty Acid (VFA) number is a measure of bacterial breakdown; higher VFA indicates spoilage and loss of stability.
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  44. 44.
    Viscosity of latex is measured using
    Show answer and explanation
    Answer: B —
    Brookfield Viscometer
    Brookfield Viscometer is widely used for measuring the viscosity of liquid systems like latex.
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  45. 45.
    Magnesium content of latex is estimated by direct titration with ______ using Erichrome Black T as indicator.
    Show answer and explanation
    Answer: C —
    0.005 M EDTA Solution
    Magnesium ions are estimated complexometrically using 0.005 M EDTA solution with Eriochrome Black T indicator.
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  46. 46.
    As per IS 5430 - 1981, the maximum permissible value for Coagulum content for preserved natural rubber latices is
    Show answer and explanation
    Answer: D —
    0.05% by mass of latex
    The maximum permissible coagulum content for preserved field and concentrated natural rubber latex according to IS standards is 0.05% by mass.
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  47. 47.
    Water soluble ingredients can be added into latex as _______.
    Show answer and explanation
    Answer: B —
    Solutions
    Water-soluble compounding ingredients are dissolved in water and added as solutions.
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  48. 48.
    Dispersions can be prepared using
    Show answer and explanation
    Answer: D —
    All the above mentioned
    Ball mills, vibration mills, and colloid mills are all used for preparing dispersions of insoluble compounding ingredients.
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  49. 49.
    TMTD is added into the latex as ________.
    Show answer and explanation
    Answer: B —
    Dispersion
    TMTD (Tetramethylthiuram disulfide) is insoluble in water and is added as an aqueous dispersion.
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  50. 50.
    Identify the creaming agent used for concentrating latex
    Show answer and explanation
    Answer: A —
    Tamarind seed powder
    Tamarind seed powder and alginates are common vegetable hydrocolloids used as creaming agents for concentrating latex.
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  51. 51.
    KOH is added to the latex compound as
    Show answer and explanation
    Answer: D —
    None of the above mentioned
    Potassium hydroxide (KOH) is completely soluble in water and is added as an aqueous solution, making 'None of the above mentioned' (since options listed are emulsions, dispersion, suspension) correct.
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  52. 52.
    Dry rubber content of field latex can be measured roughly using
    Show answer and explanation
    Answer: A —
    Metrolac meter
    Metrolac is a hydrometer calibrated to directly read the approximate Dry Rubber Content (DRC) of field latex.
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  53. 53.
    Which is used for the proper alignment of the nozzle and mold of the injection molding machine?
    Show answer and explanation
    Answer: C —
    Register ring
    The register ring on the mold locates and aligns the mold correctly with the machine nozzle.
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  54. 54.
    Which type of cooling system provides the most efficient heat exchange in the calendaring process?
    Show answer and explanation
    Answer: D —
    Peripherally drilled rolls
    Peripherally drilled rolls allow cooling fluid to flow very close to the surface, providing the most uniform and efficient heat exchange.
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  55. 55.
    Which standard system is used for the identification of the hazard material for emergency response?
    Show answer and explanation
    Answer: B —
    NFPA 704
    NFPA 704 is the standard system for the identification of the hazards of materials for emergency response.
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  56. 56.
    The chemicals, which produce suffocation from lack of oxygen are known as ______.
    Show answer and explanation
    Answer: C —
    Asphyxiants
    Asphyxiants are substances that can cause suffocation by displacing oxygen or interfering with the body's ability to use oxygen.
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  57. 57.
    LD 50 and LC 50 are the measurements of _______.
    Show answer and explanation
    Answer: B —
    toxicity
    LD50 (Lethal Dose) and LC50 (Lethal Concentration) are standard measures of the toxicity of a substance.
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  58. 58.
    Which rubber-to-metal bonding system is most suitable for large rubber roller manufacturing?
    Show answer and explanation
    Answer: B —
    Ebonite bonding
    Ebonite bonding is traditionally used for large rubber rollers to ensure a strong, durable bond between the rubber and the metal core.
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  59. 59.
    Estimations done by standard iodine solutions are called _______.
    Show answer and explanation
    Answer: B —
    Iodimetry
    Iodimetry is a direct titration method using a standard iodine solution as the titrant.
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  60. 60.
    What is the meaning of this chemical hazard symbol? Diagram🔍 Click to zoom
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    Answer: C —
    Oxidizable liquid
    The symbol typically associated with oxidizers in chemical hazard labeling represents an oxidizable substance.
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  61. 61.
    Which indicator should be used for complexometric titrations?
    Show answer and explanation
    Answer: C —
    Eriochrome black T
    Eriochrome black T is a common metal-ion indicator used in complexometric titrations, particularly for determining water hardness.
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  62. 62.
    Which intermediate solution is used in iodometry for the estimation of potassium dichromate?
    Show answer and explanation
    Answer: B —
    Sodium thiosulphate
    In iodometric titration, sodium thiosulphate is used to titrate the liberated iodine.
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  63. 63.
    The hardness of water is expressed in ______.
    Show answer and explanation
    Answer: C —
    Degrees
    Water hardness is commonly expressed in degrees of hardness (e.g., German degrees, French degrees).
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  64. 64.
    Which of the following solution should be used for eye bathing, when acids get in the eyes at the laboratory?
    Show answer and explanation
    Answer: C —
    2%
    A weak solution of sodium bicarbonate (2%) is typically used to neutralize acid splashes in the eyes.
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  65. 65.
    Solutions of a weak acid and its conjugate base or weak base and its conjugate acid can maintain pH is known as _______.
    Show answer and explanation
    Answer: D —
    Buffer
    A buffer solution resists changes in pH upon the addition of small amounts of acid or base.
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  66. 66.
    How do you make 0.1N aqueous solution?
    Show answer and explanation
    Answer: C —
    4 gm in 1000 ml water
    For NaOH (molar mass 40g/mol), 0.1N is 4g/L. Thus, 4g in 1000ml water.
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  67. 67.
    Which of the given parameter value increases with the magnesium content?
    Show answer and explanation
    Answer: D —
    Sludge content
    High magnesium content in latex leads to the formation of magnesium soaps, which increases the sludge content.
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  68. 68.
    Hearing protection is required when noise levels exceed OSHA's PEL of _____ dBA.
    Show answer and explanation
    Answer: B —
    90
    OSHA's Permissible Exposure Limit (PEL) for noise is 90 dBA for an 8-hour time-weighted average.
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  69. 69.
    Which equipment is used in the determination of the KOH Number of latex?
    Show answer and explanation
    Answer: C —
    pH meter
    A pH meter is used to monitor the titration process for determining the KOH number of latex.
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  70. 70.
    Which of the following chemical is used as a coagulating agent in the VFA number determination of latex?
    Show answer and explanation
    Answer: B —
    30% Ammonium sulfate
    30% Ammonium sulfate is commonly used as a coagulating agent in the VFA (Volatile Fatty Acid) number test.
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  71. 71.
    What is the function of an Electrostatic precipitator in industries?
    Show answer and explanation
    Answer: D —
    Device for pollution control
    Electrostatic precipitators are used to remove fine particles like dust and smoke from exhaust gases, serving as pollution control devices.
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  72. 72.
    Which of the following is most considered for approved eye protection in labs?
    Show answer and explanation
    Answer: D —
    Goggle glass meeting ANSI standard Z87
    ANSI Z87.1 is the standard for occupational and educational personal eye and face protection devices.
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  73. 73.
    Which is calculated as the percentage of the specimen's permanent deformation to its original thickness?
    Show answer and explanation
    Answer: B —
    Compression set under a constant force
    Compression set under a constant force measures the permanent deformation relative to the original thickness after a specific load is applied.
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  74. 74.
    The hazard rating diamond of a chemical label is marked 3 in the blue zone. What does this mean?
    Show answer and explanation
    Answer: D —
    The chemical is a serious health hazard
    In the NFPA 704 diamond, the blue zone represents health hazards, where 3 indicates a serious health hazard.
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  75. 75.
    Which part of analytical balance is directly linked with central agate?
    Show answer and explanation
    Answer: D —
    Lever
    The central beam or lever of an analytical balance rests on the central agate knife-edge.
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  76. 76.
    If the rider is placed at the small division from the center of the beam on the right side, then the effective mass due to the rider is _______.
    Show answer and explanation
    Answer: A —
    2 mg
    The effective mass depends on the rider weight and its position on the beam scale.
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  77. 77.
    What is the first remedy for bromine burn accidents in the laboratory?
    Show answer and explanation
    Answer: B —
    Wash with petrol and apply olive oil
    Bromine is soluble in organic solvents like petrol, which helps in removing it from the skin before applying soothing agents like olive oil.
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  78. 78.
    Which laboratory flask is used for Vacuum filtration?
    Show answer and explanation
    Answer: C —
    Buchner flask
    A Buchner flask (or side-arm flask) is specifically designed to withstand the pressure difference during vacuum filtration.
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  79. 79.
    The filled volume of an internal mixer = ________.
    Show answer and explanation
    Answer: B —
    Net chamber volume*Fill factor
    The effective volume used in an internal mixer is calculated by multiplying the net chamber volume by the fill factor.
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  80. 80.
    Which curing system is suitable for the epoxy resin to obtain high alkali resistance?
    Show answer and explanation
    Answer: C —
    Amine
    Amine-cured epoxy resins generally exhibit superior chemical resistance, including resistance to alkalis.
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  81. 81.
    What is the function of styrene in UP-resin compounding?
    Show answer and explanation
    Answer: C —
    Diluent of UP resin
    Styrene acts as a reactive diluent in unsaturated polyester (UP) resins to reduce viscosity for easier processing.
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  82. 82.
    Which catalyst is used for elevated temperature of curing of UP resin?
    Show answer and explanation
    Answer: D —
    Benzoyl peroxide
    Benzoyl peroxide is commonly used as a catalyst for high-temperature curing of unsaturated polyester resins.
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  83. 83.
    Which promotes good adhesion between fibrous reinforcement and resin matrix?
    Show answer and explanation
    Answer: C —
    Vinyl trichlorosilane
    Silane coupling agents like vinyl trichlorosilane are used to improve the bond between inorganic fibers and organic resin matrices.
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  84. 84.
    Which is used as a UV stabilizer?
    Show answer and explanation
    Answer: C —
    Benzotriazole
    Benzotriazoles are a common class of UV absorbers used to stabilize polymers against degradation.
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  85. 85.
    Which ingredient increases the tinctorial power and fastness to light of rubber product?
    Show answer and explanation
    Answer: C —
    Titanium dioxide
    Titanium dioxide is a white pigment known for its high opacity (tinctorial power) and excellent light stability.
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  86. 86.
    Which is used as a co-agent in peroxide curing of rubber?
    Show answer and explanation
    Answer: B —
    Try allyl isocyanurate
    Triallyl isocyanurate (TAIC) is a common co-agent used to enhance the crosslinking efficiency of peroxide curing systems.
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  87. 87.
    What is the function of ethylene thio urea in Chloroprene rubber compounding?
    Show answer and explanation
    Answer: B —
    Accelerator
    Ethylene thiourea (ETU) is the standard accelerator used for the vulcanization of polychloroprene (neoprene) rubber.
    Report a mistake
  88. 88.
    Which type of carbon black increases the conductivity of rubber compounds?
    Show answer and explanation
    Answer: A —
    Acetylene black
    Acetylene black has a high structure and purity, making it highly effective at increasing the electrical conductivity of rubber.
    Report a mistake
  89. 89.
    Which is the most suitable reinforcing filler for fluorocarbon rubbers?
    Show answer and explanation
    Answer: C —
    Medium thermal black
    Medium thermal (MT) black is widely used as a reinforcing filler for fluorocarbon rubbers due to its low surface area and chemical compatibility.
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  90. 90.
    Which curing system is suitable for saturated rubbers for high-temperature resistance?
    Show answer and explanation
    Answer: C —
    Peroxide
    Peroxide curing systems create carbon-carbon crosslinks, which are more thermally stable than the sulfur-based crosslinks found in unsaturated rubbers.
    Report a mistake

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