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(A) Urea formaldehyde resin can be reuse...

(A) Urea formaldehyde resin can be reused again even on strong heating.
(R) Urea formaldehyde resin is a Thermo- plastic polymer.

A

Both (A) and (R) are true and (R) is the correct explanation of (A)

B

Both (A) and (R) are true and (R) is not the correct explanation of (A)

C

(A) is true but (R) is false

D

Both (A) and (R) are false

Text Solution

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The correct Answer is:
D
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Based on the behaviour of polymer it can be classified int two forms i.e. thermo plastic polymers and thermosetting polymers. The thermo plastics canbe softened (or) plasticized repeated by on application of thermal energy. The thermo setting polymers can be obtained in soluble and fusible forms in early (or) intermediate stages of their synthesis but they get secured and become insoluble and infusible when further heated (or) thermally heated. Thermo plastic polymers are formed by

Based on the behaviour of polymer it can be classified int two forms i.e. thermo plastic polymers and thermosetting polymers. The thermo plastics canbe softened (or) plasticized repeated by on application of thermal energy. The thermo setting polymers can be obtained in soluble and fusible forms in early (or) intermediate stages of their synthesis but they get secured and become insoluble and infusible when further heated (or) thermally heated. (1) Thermosets donot soften on heating (2) Thermo plastic soften on heating and stiffen on cooling

Based on the behaviour of polymer it can be classified int two forms i.e. thermo plastic polymers and thermosetting polymers. The thermo plastics canbe softened (or) plasticized repeated by on application of thermal energy. The thermo setting polymers can be obtained in soluble and fusible forms in early (or) intermediate stages of their synthesis but they get secured and become insoluble and infusible when further heated (or) thermally heated. Thermosets can have

Polymers containing -CONH- linkage among , nylon, bakelite, urea formaldehyde resin, buna-s, neoprene, natural rubber, proteins.

(A) Bakelite is prepared by copolymerisation of formaldehyde and phenol. (R) Adding of phenol with formaldehyde gives polymer bakelite.

Nitric oxide (NO) is the nucleus of photochemical smog. 2NO(g) + O_(2) ("air") rarr 2NO_(2) (g) NO_(2)(g) overset("Sunlight")(rarr) NO(g) + [O] [O] + O_(2) (g) rarr O_(3)(g) Both NO_(2) and O_(3) are strong oxidising agents and react with unburnt hydrocarbons in the polluted air to produce formaldehyde, acrolein and peroxyacetyl nitrate (PAN). These products are harmful to the plant and animal life. Catalytic converters are now installed in the automobiles to reduce the photochemical smog. Photochemical smog can also be supressed by certain compounds, which act as free radical trap. Smog is common pollutant in places having :

Nitric oxide (NO) is the nucleus of photochemical smog. 2NO(g) + O_(2) ("air") rarr 2NO_(2) (g) NO_(2)(g) overset("Sunlight")(rarr) NO(g) + [O] [O] + O_(2) (g) rarr O_(3)(g) Both NO_(2) and O_(3) are strong oxidising agents and react with unburnt hydrocarbons in the polluted air to produce formaldehyde, acrolein and peroxyacetyl nitrate (PAN). These products are harmful to the plant and animal life. Catalytic converters are now installed in the automobiles to reduce the photochemical smog. Photochemical smog can also be supressed by certain compounds, which act as free radical trap. Photochemical transformation of the automobile exhaust emission in UV wavelength of sunlight results into

Nitric oxide (NO) is the nucleus of photochemical smog. 2NO(g) + O_(2) ("air") rarr 2NO_(2) (g) NO_(2)(g) overset("Sunlight")(rarr) NO(g) + [O] [O] + O_(2) (g) rarr O_(3)(g) Both NO_(2) and O_(3) are strong oxidising agents and react with unburnt hydrocarbons in the polluted air to produce formaldehyde, acrolein and peroxyacetyl nitrate (PAN). These products are harmful to the plant and animal life. Catalytic converters are now installed in the automobiles to reduce the photochemical smog. Photochemical smog can also be supressed by certain compounds, which act as free radical trap. Which are the primary constituents of photochemical smog ?

AAKASH SERIES-POLYMERS-OBJECTIVE EXERCISE - 4
  1. (A) Poly styrene is a Thermoplastic polymer. (R) Polystyrene softens...

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  2. (A) Bakelite is a Thermoplastic polymer. (R) Bakelite is a linear po...

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  3. (A) Urea formaldehyde resin can be reused again even on strong heating...

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  4. (A) Addition polymerisation is also known as step growth polymerisatio...

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  5. (A) Poly lactic acid is a condensation copolymer. (R) Poly lactic ac...

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  6. (A) AICI(3) can initiate cationic polymerisation. (R) AICI(2) can pr...

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  7. (A) In Anionic polymerization chain terminating step is absent. (R) ...

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  8. (A) Benzoyl peroxide can initiate free radical polymerisation. (R) ...

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  9. (A) Ethylene can not be prepared by anionic polymerisation. (R) Eth...

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  10. (A) Teflon is used in nonstick cookwere (R) Teflon is resistant to a...

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  11. (A) Condensation polymeristion is called step growth polymerisation. ...

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  12. (A) Nylon-6 is condensation homo polymer. (R) Nylon-6 is a fibre.

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  13. (A) Dacron is used as reinforcing material in safety helmets. (R) Da...

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  14. (A) Novolac is a linear polymer. (R) Bakelite is obtained from novol...

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  15. (A) Melamine is a thermosetting polymer (R) Melamine is a condensati...

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  16. (A) Melamine polymers are used to prepare unbreakable crockery items. ...

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  17. (A) Vulcanised Rubber suits industry than natural Rubber. (R) Elasti...

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  18. (A) Rubber latex is colloidal dispersion in water with negatively char...

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  19. (A) Ebonite contain a high percentage of sulphur. (R) Ebonite is a h...

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  20. (A) The process of vulcanization can be accelerated by Zno or zinc ace...

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