Description : Plasticisers are added to synthetic plastics to (A) Impart flexibility (B) Improve workability during fabrication (C) Develop new improved properties not present in the original resin (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Plasticisers are added to polymers to improve their (A) Tensile strength (B) Softness & flexibility (C) Acid resistance (D) Alkali resistance
Last Answer : (B) Softness & flexibility
Description : Plasticisers are added to synthetic plastics to (A) Impart flexibility (B) Improve workability during fabrication (C) Develop new improved properties not present in the original resins (D) All (A), (B) and (C)
Description : . Plasticisers are added to paints to (A) Make it corrosion resistant (B) Make glossy surface (C) Give elasticity & prevent cracking of the film (D) Increase atmospheric oxidation
Last Answer : (C) Give elasticity & prevent cracking of the film
Description : Pick out the correct statement. (A) Hot worked materials are subjected to annealing to remove internal stresses (B) Annealing of steel hardens it slightly (C) Normalising of a material induces stresses (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness
Last Answer : (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness Share
Description : Pick out the wrong statement. (A) At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature (B) Normally, the gases which are easily liquefied are more soluble ... (D) At constant pressure, solubility of a gas in a liquid increases with rise in temperature
Last Answer : (A) At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature
Description : Plasticisers are high boiling liquids added to plastic polymers to impart toughness and flexibility at ordinary temperature. Which of the following is not a plasticiser? (A) Ethylene glycol (B) Stearic acid estors (C) Tricresyl phosphate (D) Esters of phthalic acid
Last Answer : (A) Ethylene glycol
Description : Glyptal used in the manufacture of paints & lacquers is a __________ polymer. (A) Polyamide (B) Polystyrene (C) Polyester (D) Polyacrylonitril
Last Answer : (C) Polyester
Description : Alkyd resin cannot be used for making (A) Plasticiser (B) Paint & varnish (C) Fibres (D) Film forming materials
Last Answer : (C) Fibres
Description : Alkyd resin e.g., glyptal resin formed by Phthalic anhydride and glycerine is not used (A) For surface coating of automobiles & air crafts (B) For fibre making (C) As plasticiser for PVC & nitrocellulose (D) For film forming materials
Last Answer : (B) For fibre making
Description : Function of thinner in a paint is to (A) Accelerate the oxidation of oil (B) Prevent gelling of the paint (C) Suspend pigments & dissolve film forming materials (D) Form a protective film
Last Answer : (C) Suspend pigments & dissolve film forming materials
Description : Glycol added to petrol acts as a/an __________ agent. (A) Anti-knocking (B) Anti-icing (C) Anti-gum forming (D) Dewaxing
Last Answer : (B) Anti-icing
Description : __________ is a non volatile film forming constituent of a paint. (A) Thinner (B) Dryer (C) Drying oil (D) None of these
Last Answer : (C) Drying oil
Description : Sulphuric acid treatment of petroleum products removes the __________ materials. (A) Gum forming (B) Color forming (C) Asphaltic (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : A polymer is used for making paints and lacquers, name it.
Last Answer : Ans: Glyptal.
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 : Elimination of brittleness resulting from welding of saw blades is done by __________ of the welded portion. (A) Annealing (B) Toughening (C) Work hardening (D) Tempering
Last Answer : (A) Annealing
Description : Temper brittleness of a material can be fairly detected by the __________ test. (A) Fatigue (B) Notched bar impact (C) Tensile (D) Hardness
Last Answer : Option B
Description : Phthalic anhydride is used (A) In making PVC (B) As plasticisers (C) In insecticides manufacture (D) For making nylon-6
Last Answer : (B) As plasticisers
Description : Addition of plasticisers to polymers results in partial neutralisation of intermolecular forces of attraction between the macro-molecules thereby increasing its (A) Tensile strength (B) Chemical resistance (C) Flexibility (D) All (A), (B) & (C)
Last Answer : (C) Flexibility
Description : Phosphates (e.g., tricresyl, tributyl, tetrabutyl, triphenyl etc.) are addedto polymers to act as (A) Hardeners (B) Anti-shrinkage agents (C) Plasticisers (D) Transparency improver
Last Answer : (C) Plasticisers
Description : Parathion and Malathion are (A) Pesticides (B) Plasticisers for unsaturated polyesters (C) Pain-relieving drugs (analgesic) (D) Tranquilisers
Last Answer : (A) Pesticides
Description : Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator? (A) Long vertical evaporator (B) Horizontal tube evaporator (C) Agitated film evaporator (D) Calandria vertical tube evaporator
Last Answer : (C) Agitated film evaporator
Description : The amount of tetraethyl lead added to improve the octane number of motor gasoline is around __________ c.c per gallon of petrol. (A) 3 (B) 300 (C) 3000 (D) 1000
Last Answer : (A) 3
Description : Thermosetting plastic materials (A) Can be repeatedly melted (B) Is useful for melt casting (C) Cannot be melted after forming (D) Is useful for spinning
Last Answer : (C) Cannot be melted after forming
Description : A steam carrying pipeline is insulated with two layers of insulating materials with the inferior insulation material forming the inner part. If the two insulating layers are interchanged, the heat conducted ... ) Remain unaffected (D) May increase or decrease; depends on the thickness of each layer
Last Answer : Option C
Description : Normalising does not __________ of a metal. (A) Improve machinability & tensile strength (B) Remove internal stresses (C) Refine the structure (D) Remove strains caused by cold working
Description : Kaolin is — type antitranspirant a. Stomata closing b. film forming c. Reflecting type d. Growth retardants
Last Answer : c. Reflecting type
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 : With increase in carbide/graphite ratio in cast iron, its (A) Hardness & brittleness increases (B) Ductility decreases (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Cast iron has very high (A) Compressive strength (B) Ductility (C) Shock resistance (D) Resistance to brittleness
Last Answer : (A) Compressive strength
Description : The ability of a material to absorb energy in the elastic range is a measure of its (A) Toughness (B) Resilience (C) Malleability (D) Brittleness
Last Answer : (B) Resilience
Description : Percentage elongation of a material is a measure of its (A) Ductility (B) Brittleness (C) Toughness (D) Malleability
Last Answer : (A) Ductility
Description : The ability of a material to offer resistance to scratching or indentation is a measure of its (A) Brittleness (B) Toughness (C) Hardness (D) Resilience
Last Answer : (C) Hardness
Description : Molybdenum steels containing 0.15 to 0.40% molybdenum (A) Are prone to temper brittleness (B) Are used for automobile parts like gears, axle, shaft, bearings etc. (C) Have very poor fatigue resistance
Last Answer : (B) Are used for automobile parts like gears, axle, shaft, bearings etc
Description : Higher percentage of ash in coal meant for the production of metallurgical grade coke (A) Decreases the hardness of coke (B) Decreases the abrasion resistance of coke (C) Causes brittleness in steel (D) None of these
Last Answer : (D) None of these
Description : High amount of sulphur and phosphorous in coke causes (A) Decrease in its calorific value (B) Increase in its strength (C) Brittleness of steel made by using it (D) None of these
Last Answer : (C) Brittleness of steel made by using it
Description : Increasing the carbon content of steel (A) Reduces the upper shelf energy (B) Increasing the ductility transition temperature (C) Decreases brittleness (D) Decreases hardness
Last Answer : (B) Increasing the ductility transition temperature
Description : Fine grained steels have (A) High brittleness (B) Higher tendency to distort (C) High ductility (D) None of these
Last Answer : (C) High ductility
Description : Brittleness induced due to the presence of sulphur in steel can be reduced by adding (A) Manganese (B) Magnesium (C) Vanadium (D) Copper
Last Answer : (A) Manganese
Last Answer : r: Option A
Description : Sub zero treatment of steel is done to (A) Suppress martensite transformation (B) Enhance its working performance in sub zero atmosphere (C) Reduce the retained austenite in hardened steel (D) Induce temper brittleness after its hardening
Description : Between 230 and 370°C, blue brittleness is caused in mild steel because of the (A) Immobility of dislocation (B) Strain-ageing (C) Increase in Young's modulus (D) Strain hardening
Description : When paternal and maternal chromosomes change their materials with each other in cell division this event is called (a) bivalent-forming (b) dyad-forming (c) synapsis (d) crossing-over.
Last Answer : (d) crossing-over.
Description : Thermosetting resins/polymers as compared to thermoplastic ones are (A) Soluble in all organic solvents (B) More brittle (C) Formed by addition polymerisation only (D) Easily reshaped & reused
Last Answer : (B) More brittle
Description : Vulcanisation of rubber decreases its (A) Tensile strength (B) Resistance to organic solvents (C) Tackiness (D) Working temperature range
Last Answer : (C) Tackiness
Description : Pick out the wrong statement regarding the solubility characteristics of high polymers. (A) Greater the degree of cross-linking in the polymer, lesser is its solubility (B) Polymers having more ... of the solvent (D) High molecular weight polymers on dissolving gives solution of very low viscosity
Last Answer : (D) High molecular weight polymers on dissolving gives solution of very low viscosity
Description : Neoprene which is used for making shoe heels & belts is superior to natural rubber in its stability to aerial oxidation and resistance to oils & other solvents. The monomer used for making neoprene is (A) Chloroethane (B) Chloroprene (C) Isoprene (D) None of these
Last Answer : (B) Chloroprene