Saved Bookmarks
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 25702. |
The polymers obtained by the addition polymerisation of two different monomers are termed as____________. |
| Answer» SOLUTION :COPOLYMERS | |
| 25703. |
The polymers obtained from the monomers phenol and formaldehyde are |
|
Answer» polythene |
|
| 25704. |
The polymerization of ethylene to linear polyethylene is represented by the reaction nCH_2 = CH_2 to (-CH_2 - CH_2 - )_nwhere n has large integral value. Given that the average enthalpies of bond dissociation for C=C and C-C at 298 K are +590 and +331 kJ "mole"^(-1)respectively, calculate the enthalpy of polymerization per mole of ethylene at 298 K. |
|
Answer» SOLUTION :`DELTA H = 1 XX 590- 2 xx 331` -72kJ |
|
| 25706. |
The polymer with high tensile strength and high modulus are known as …….. |
|
Answer» FIBRES |
|
| 25707. |
The polymer which undergoes environment degradation by microorganism is known as |
|
Answer» CHAIN GROWTH polymer |
|
| 25708. |
The polymer used in the valve packing |
|
Answer» TEFLON |
|
| 25709. |
The polymerwhich can be easily softeningon heating and hard on cooling is |
|
Answer» NEOPRENE |
|
| 25710. |
The polymer which can stretched easily by applying small stress and return to it'soriginal shape when stress is removed |
| Answer» ANSWER :A | |
| 25711. |
The polymer used in the squeze bottles is |
|
Answer» Polystyrene |
|
| 25712. |
The polymer used in making blankets (artificial wool) is |
|
Answer» polystyrene |
|
| 25713. |
The polymer used in orthopedic devices and in controlled drug release is S : |
|
Answer» ORLON |
|
| 25714. |
The polymer used in the manufacture of electrical goods such as switches, plugs etc is |
|
Answer» Polythene |
|
| 25715. |
The polymer used in making blankets(artificial wool) is |
|
Answer» polystyrene |
|
| 25716. |
The polymer used for making unbreakable cups and laminated sheets |
|
Answer» POLYSTYRENE |
|
| 25717. |
The polymer PMMA is used for making ....................and its monomer is. |
|
Answer» |
|
| 25718. |
The polymer obtained from condensation of sebacic acid and hexamethylene diammine is called: |
|
Answer» Terylene |
|
| 25719. |
The polymer polystyrene has the repeating unit : |
|
Answer» `-CH_2-UNDERSET(CN)underset(|)(CH)-` |
|
| 25720. |
The polymer obtained by step-growth polymerization of 2-aminoethanoic acid and 6- aminohexanoic acid is called .................... |
|
Answer» |
|
| 25721. |
The polymer of 1,3-butadiene and acrylonitrile is called |
|
Answer» BUNA - s - rubber |
|
| 25722. |
The polymer having strongest intemolecular forces is |
|
Answer» Fibres |
|
| 25723. |
The polymer formed with more than two monosaccharide unit is known as : |
|
Answer» DISACCHARIDE |
|
| 25724. |
The polymer containing strong intermolecular forces e.g. hydrogen bonding is |
|
Answer» NATURAL rubber |
|
| 25725. |
The polymer containing strong intermolecular forces e.g. hydrogen bonding, is |
|
Answer» teflon |
|
| 25726. |
The polymer containing strong intermolecular forces, |
|
Answer» BUNA S rubber |
|
| 25727. |
The polymer containing strong intermolecular forces :- |
|
Answer» Buna S RUBBER |
|
| 25728. |
The polymer containing five methylene groups in its repeating unit is |
|
Answer» nylon-6, 6 Nylon-6 |
|
| 25729. |
Thepolymer acrilan has the repeating unit . |
|
Answer» `-CH_2-OVERSET(CN)overset(|)CH-` |
|
| 25730. |
The polymer containing an arnide group is : |
|
Answer» POLYTHENE |
|
| 25731. |
The polydispersity index of a polymer containing 10 molecules with moleculer mass 1.0xx10^(4) and 10 molecules with moleculer mass 1.0xx10^(5) is approximately . |
|
Answer» 1.67 |
|
| 25732. |
Thepollution whichcomedirectly in the air from sourcesare calledprimarypollutants . Primarypollutantsaresometimesconvertedintosecondarypollutants. Whichofthe followingbelongto secondary airpollution ? |
|
Answer» CO |
|
| 25733. |
The polydentate ligand used in the treatment of lead poisoning |
|
Answer» EDTA |
|
| 25734. |
The pollution in city like Delhi may be controlled to great extent |
|
Answer» By PROPER sewage and proper exit of chemicals from factories |
|
| 25735. |
The pollutants emitted by jet aeroplanes in outer atmosphere are known as |
|
Answer» Loess |
|
| 25736. |
The polarity of the carbon-halogen bond is responsible for the nucleophilic substitution reactions of alkyl halides which mostly occur by S_(N)1 and S_(N)2 mechanisms. The rates of S_(N)2 reactions among other things are governed by steric factors while than of S_(N)1 reactions are governed by the stability of intermediate carbocations. chirality has a profound role in undersetanding the mechanism of S_(N)1 and S_(N)2 reactions. whereas S_(N)2 reactions of chiral alkyl halides are accompanied by inversion of configuration, S_(N)1 reactions are characterised by racemisation. Q. In the solvolysis of 3-methyl-3-bromohexane, which of the followin statements is not correct? |
|
Answer» it involves CARBOCATION INTERMEDIATE  
|
|
| 25737. |
The polarity of the carbon-halogen bond is responsible for the nucleophilic substitution reactions of alkyl halides which mostly occur by S_(N)1 and S_(N)2 mechanisms. The rates of S_(N)2 reactions among other things are governed by steric factors while than of S_(N)1 reactions are governed by the stability of intermediate carbocations. chirality has a profound role in undersetanding the mechanism of S_(N)1 and S_(N)2 reactions. whereas S_(N)2 reactions of chiral alkyl halides are accompanied by inversion of configuration, S_(N)1 reactions are characterised by racemisation. Q. An S_(N)2 reaction at an asymmetric carbon of a compound always gives |
|
Answer» an enantiomer of the substrate |
|
| 25738. |
The polarizibility of the following compounds is/are |
|
Answer» `I^(-) GT Br^(-) gt Cl^(-) gt F^(-)` |
|
| 25739. |
The polarity of the carbon-halogen bond is responsible for the nucleophilic substitution reactions of alkyl halides which mostly occur by S_(N)1 and S_(N)2 mechanisms. The rates of S_(N)2 reactions among other things are governed by steric factors while than of S_(N)1 reactions are governed by the stability of intermediate carbocations. chirality has a profound role in undersetanding the mechanism of S_(N)1 and S_(N)2 reactions. whereas S_(N)2 reactions of chiral alkyl halides are accompanied by inversion of configuration, S_(N)1 reactions are characterised by racemisation. Q. S_(N)1 reaction of optically active alkyl halides leads to |
|
Answer» RETENTION of configuration |
|
| 25740. |
The polarity of the carbon-halogen bond is responsible for the nucleophilic substitution reactions of alkyl halides which mostly occur by S_(N)1 and S_(N)2 mechanisms. The rates of S_(N)2 reactions among other things are governed by steric factors while than of S_(N)1 reactions are governed by the stability of intermediate carbocations. chirality has a profound role in undersetanding the mechanism of S_(N)1 and S_(N)2 reactions. whereas S_(N)2 reactions of chiral alkyl halides are accompanied by inversion of configuration, S_(N)1 reactions are characterised by racemisation. Q. Which of the following is an example of S_(N)2 reaction? |
|
Answer» `CH_(3)Br+OH^(-)toCH_(3)OH+Br^(-)` |
|
| 25741. |
The polarity is maximum in : |
|
Answer» N-F |
|
| 25742. |
The polarimeter readings in an experiment to measure the rate of inversion of cane sugar (1st order reaction) were as follows {:("time(min)",:,0,30,oo),("angle(degree)",:,30,20,-15):} Identify the true statement(s) ? [log2=0.3,log 3=0.48, log 7=0.84, log_e10=2.3] |
|
Answer» The HALF LIFE of the reaction is 75 min `k=1/30 2.3"log"(30-(-15))/(20-(-15))=1/30"log"45/35` `:. T_(1//2)75` min `k=1/t2.3 "log"45/(0-(-15))` t=120 min `(30-(-15))/(x-(x-15))=2` at half time `IMPLIES 45(x+15)=2 implies x+15=45/2implies x=22.5-15=7.5^@` |
|
| 25743. |
The poissons ratio for inert gases is : |
|
Answer» 1.40 |
|
| 25744. |
The points noted by arrows are melting and boiling points of the metal zinc and magnasium. Delta G^(0) as a function of temperature for some reaction of extractive metallurgy. At 1000^(@)C, which reaction is spontaneous to a maximum extent |
|
Answer» `MgO+C RARR Mg+CO` |
|
| 25745. |
The poisonous gas evolved in Bhopal tragedy from the pesticide plant of union carbide was |
|
Answer» `CH_3NCO` |
|
| 25746. |
The points noted by arrows are melting and boiling points of the metal zinc and magnasium. Delta G^(0) as a function of temperature for some reaction of extractive metallurgy. At what approximate temprature, zinc and carbon have equal affinity for oxygen? |
|
Answer» `1000^(@)`C |
|
| 25747. |
The point of dissimilarity between (SO_(3) )_( 3)and (HPO_(3))_(3)(cyclic trimer) is :- |
|
Answer» Both have six MEMBERED ring. |
|
| 25748. |
The pOH of beer is 10.0. The hydrogen ion concentration will be |
|
Answer» `10^(-2)` |
|
| 25749. |
What will be the pOH of 0.5xx10^(-4)M H_(2)SO_(4) solution ? |
|
Answer» 4 |
|
| 25750. |
The plots of triangleG versus T in the metallurgical processes are called |
|
Answer» HELMHOLTZ diagram |
|