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 : 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 : Thermosetting polymers as compared to thermoplastic polymers (A) Are formed by addition polymerisation (B) Have three dimensional structure (C) Have linear structure (D) None of these
Last Answer : (B) Have three dimensional structure
Description : While the thermosetting polymers are amorphous in nature, the thermoplastic polymers are either amorphous or crystalline. The crystalline polymers are characterised by the (A) Low impact strength (B) High flexibility (C) Better finish and surface appearance (D) High plastic deformation
Last Answer : A) Low impact strength
Description : Cross linked polymers are (A) Thermoplastic (B) Thermosetting (C) Either (A) or (B) (D) Fibres only
Last Answer : (B) Thermosetting
Description : Polymers are classified into four categories namely thermosetting, thermoplastic, elastomer and fibre depending upon their (A) Molecular sizes (B) Magnitude of intermolecular forces (C) Resistance to heat (D) Polymerisation mechanism
Last Answer : (B) Magnitude of intermolecular forces
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 : Differentiate between Thermoplastic and Thermosetting polymers.
Last Answer : Differentiate between Thermosetting and Thermoplastic polymers: Thermosetting Thermoplastic Polymers which once mould /shaped do not soften when heated and thus cannot be reshaped Polymers whose ... tri, tetra or poly functional. Monomer used in this polymer bi functional.
Description : Polymethyl methacrylate (PMMA) which is also known as Perspex and is produced by bulk polymerisation of methyl methacrylate is not a __________ polymer. (A) Thermoplastic (B) Thermosetting (C) Linear (D) Glass like transparent
Description : Polycondensation reaction of polymerisation (A) Does not produce linear polymers (B) Produces only thermoplastic material (C) Produces epoxy polymers (D) Does not need any catalyst
Last Answer : (C) Produces epoxy polymers
Description : Polyvinyl chloride (PVC) (A) Is produced by Polycondensation reaction (B) Uses either emulsion or suspension polymerisation methods (C) Can be made thermosetting by adding a plasticiser (D) Softening temperature is 200°C
Last Answer : (B) Uses either emulsion or suspension polymerisation methods
Description : Poly Vinyl chloride (PVC) is a __________ material. (A) Thermoplastic (B) Thermosetting (C) Fibrous (D) Chemically active
Last Answer : (A) Thermoplastic
Description : All thermoplastic, thermosetting & elastic materials can be processed in a extrusion machine, however it cannot be used for the production of plastic (A) Filaments (B) Pipes (C) Buckets (D) Tubings
Last Answer : (C) Buckets
Description : Thermoplastic resins usually (A) Remain hard as long as they are hot (B) Cannot be reclaimed from waste (C) Permanent setting resins (D) Less brittle than thermosetting resins
Last Answer : (D) Less brittle than thermosetting resins
Description : Poly Vinyl Chloride (P.V.C.) is a __________ material. (A) Thermosetting (B) Thermoplastic (C) Fibrous (D) Chemically active
Last Answer : (B) Thermoplastic
Description : Fibre reinforced plastic (FRP) are (A) Made of glass fibre and thermoplastic resins (B) Anisotropic (C) Made of thermosetting resin and glass fibre (D) Both 'b' & 'c'
Last Answer : Option D
Description : Thermoplastic resins are those polymers, which (A) Has decreased plasticity at increasing temperature (B) Cannot be moulded (C) Easily deform under pressure at high temperature (D) None of these
Last Answer : (C) Easily deform under pressure at high temperature
Description : Differentiate between thermosetting and thermo-softening plastics.
Last Answer : Thermosetting Thermo-softening 1. The plastics who possess three dimensional complicated structure with cross linkages are called as thermo setting plastics 1. The plastics who possess ... , Urea formaldehyde, Silicon plastic 11. Examples- Polythene, Polystyrene, PVC, Teflon
Description : Compare between thermoplastic and thermosetting plastic.
Last Answer : Thermoplastics Thermosetting They can be repeated softened by heat and hardened on cooling Once hardened and set they do not softened with application of heat They are formed by ... to soft under heat They can be used at comparatively higher temperature without damage.
Description : Pick out the wrong statement. (A) Polymeric fibres are never produced by addition polymerisation (B) Property of tackiness is exhibited by uncured rubber (C) Sharp melting point is not observed in thermoplastic polymers (D) Polythene generally has an excellent resistance to ultra violet rays
Last Answer : (A) Polymeric fibres are never produced by addition polymerisation
Description : Which of the following types of polymers has the strongest inter particle forces? (A) Elastomers (B) Fibres (C) Thermoplastics (D) Thermosetting polymers
Last Answer : (D) Thermosetting polymers
Description : Thermosetting resins are those polymers, which (A) Do not increase in plasticity with rise in temperature (B) Allow slip to occur between molecules (C) Do not take on a permanent set (D) None of these
Last Answer : (A) Do not increase in plasticity with rise in temperature
Description : Thermosetting polymers are (A) Injection moulded (B) Cast molded (C) Extruded (D) None of these
Last Answer : (B) Cast molded
Description : Distinguish between thermoplastic and thermo setting polymers.
Last Answer : Thermo plastic polymer Thermo setting plastic 1. The inter moliculer forces are intermediate. 1. The inter molecular force are ... 3. Eg. Polythene and polystyrene 3. Eg. Bakelite
Description : Polymers which soften on heating and harden when cooled are (a) Cross-linked polymers (b) Copolymers (c) Thermosetting polymers (d) Thermoplastics
Last Answer : Thermoplastics
Description : List any four properties of thermosetting polymers.
Last Answer : Properties of thermosetting polymers: 1.Very poor elasticity 2.sronger attractive forces between chains 3. not soluble in organic compounds 4.can not be remoulded 5. these polymers produces by condensation polymerization
Description : Paraffins are desirable in lubricating oil, as it has got high (A) Viscosity (B) Viscosity index (C) Smoke point (D) Pour poin
Last Answer : (C) Smoke point
Description : Branched chain polymers compared to linear polymers have higher (A) Density (B) Tensile strength (C) Melting point (D) Degree of irregularity in atomic packing
Last Answer : (D) Degree of irregularity in atomic packing
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 : Branched chair polymers as compared to linear polymers have (A) Higher melting point (B) Higher tensile strength (C) Lower density (D) None of these
Last Answer : (C) Lower density
Description : Elastomers are (A) Thermosetting material (B) Exemplified by protein derivatives (C) Having high flexural strength (D) Having very high tensile strength and heat resistance
Last Answer : (C) Having high flexural strength
Description : The accelerometer is used as a transducer to measure earthquake in Richter scale. Its design is based on the principle that ______. (A) its natural frequency is very low in comparison to the ... is equal to the frequency of vibration (D) measurement of vibratory motion is without any reference poin
Last Answer : (C) its natural frequency is equal to the frequency of vibration
Description : The accelerometer is used as a transducer to measure earthquake in Richter scale. Its design is based on the principle that a) its natural frequency is very low in comparison to the frequency ... is equal to the frequency of vibration d) measurement of vibratory motion is without any reference poin
Last Answer : c) its natural frequency is equal to the frequency of vibration
Description : The most important property for a jet fuel is its (A) Viscosity (B) Freezing point (C) Calorific value (D) Flash poin
Last Answer : (B) Freezing point
Description : Pick out the wrong statement. (A) Surface tension of a liquid is because of the difference in magnitude of adhesive & cohesive forces (B) A hydrometer used for the determination of ... Turbulent fluid flow is characterised by the rapid fluctuation of instantaneous pressure & velocity at a poin
Last Answer : (C) In case of unsteady fluid flow, the velocity at any given point does not change with time
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 : At yield point' of a copper wire A. the load hasn't exceeded the elastic limit yet; so, Hooke's law applies B. the load has already exceeded the elastic limit and the material has become ... stage has passed and the wire has snapped already D. Like Brass and Bronze, Copper has no yield poin
Last Answer : the load has already exceeded the elastic limit and the material has become plastic
Description : In cold countries ethylene glycol is added to water in car radiators. This helps to (a) Reduce the viscosity (b) Make water a better lubricant (c) Lower the freezing point (d) Lower the boiling poin
Last Answer : Lower the freezing point
Description : A bus can travel 25% faster than a van. Both start from a certain shop at the same time and reach poin P, 37.5 kms away from the shop at the same time time. On the way, however, the bus lost about 6.25 mins while shopping at the some such places. The speed of the van is. a) 72 b) 73 c) 74 d) 75
Last Answer : A Let speed of the car be x kmph The speed of the train = 125x/100 =5x/4 km/hr Therefore 37.5 / x – 37.5 /(5x/4) = 6.25 /60 37.5 / x – (37.5*4)/5x = 6.25 / 60 37.5 / x – 150 / 5x = 6.25 / 60 37.5 / x – 30/x = 6.25 / 60 7.5 / x = 6.25 / 60 6.25x = 7.5*60 X=72 km/hr
Description : Softening point of high density polythene is about __________ °C. (A) 85 (B) 135 (C) 165 (D) 205
Last Answer : (B) 135
Description : The ability of tool steel to resist softening at high temperatures is termed as __________ hardness. (A) Red (B) Extended (C) Super (D) Extreme
Last Answer : (C) Super
Description : A material is capable of resisting softening at high temperature, because of its property termed as (A) Hot temper (B) Hot hardness (C) Fatigue (D) Creep
Last Answer : (B) Hot hardness
Description : Polymerisation of poly functional monomers produces polymers having (A) Good mechanical strength (B) Low viscosity (C) Low melting point (D) None of these
Last Answer : (A) Good mechanical strength
Description : Pick out the wrong statement. (A) Copper is the metal having the highest electronic conductivity (B) Hardenability & Weldability of metals are inversely related (C) Covalent bonding formed by ... all semiconductor materials (D) Glass transition temperature applies to 'polymers' but not to 'glasses'
Last Answer : Option A
Description : “Rate of softening of water in Ion Exchange method is high,” Give reason.
Last Answer : Rate of softening of water in ion exchange method is high because, cation exchange beds and anions exchange beds are used this process, which remove all the hardness causing substances. It also removes alkali metals. This process is useful for acidic as well as alkaline water.
Description : Mastication of rubber means (A) Its softening (B) A treatment to retard its deterioration due to oxidation (C) Improving its curing rate (D) Depression of its freezing point
Last Answer : (A) Its softening
Description : __________ test is done to find out the softening point of bitumen. (A) Impact (B) Ball and ring (C) Flame (D) Viscosity
Last Answer : (B) Ball and ring
Description : Which of the following heat treatment processes is used for softening the hardened material? (A) Normalising (B) Tempering (C) Annealing (D) None of these
Last Answer : (B) Tempering
Description : Softening of hardened steel is done by its (A) Normalising (B) Tempering (C) Annealing (D) Carburising
Description : To improve the machinability of steel by its softening, it is subjected to (A) Cold working (B) Annealing (C) Shot blasting (D) Heating
Last Answer : (B) Annealing