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प्रश्न
Write the reaction involved in the formation of bakelite.
How are the following prepared?
Bakelite
How is bakelite made?
How is bakelite synthesised?
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उत्तर १
Step 1:
Step 2:
Step 3:
उत्तर २
When formaldehyde and phenol react with a basic catalyst present, phenol-formaldehyde resins are created. Methylene bridges can develop at ortho, para, or both ortho and para locations during the process. This allows for the preparation of phenol-formaldehyde resin, often known as bakelite, a linear or cross-linked polymer.
Novolac is a linear polymer used in paints. Novolac undergoes cross-linking when heated with formaldehyde, forming an infusible solid mass known as Bakelite.
Notes
Students should refer to the answer according to their questions.
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संबंधित प्रश्न
Explain the following term: Homopolymers
Write the formulae of the raw materials used for preparation of Dextran.
Write the monomers of the following polymer :
Choose the correct option from the given alternatives.
Which of the following is made up of polyamides?
Answer the following in one sentence.
Identify 'A' in the following reaction:
Answer the following in one sentence.
What type of intermolecular force leads to high-density polymer?
Answer the following.
Match the following pairs:
| Name of polymer | Monomer |
| 1. Teflon | a. CH2 = CH2 |
| 2. PVC | b. CF2 = CF2 |
| 3. Polyester | c. CH2 = CHCl |
| 4. Polythene | d. C6H5OH and HCHO |
| 5. Bakelite | e. Dicarboxylic acid and polyhydoxyglycol |
Answer the following.
Draw the structures of polymers formed from the following monomers
H2N–(CH2)5 – COOH
Identify condensation polymers and addition polymers from the following.
\[\begin{array}{cc}\ce{-(CH2 - CH -)_{n}}\\
\phantom{....}|\\\ce{\phantom{.......}C6H5}
\end{array}\]
Answer the following.
Write main specialities of Buna-S, Neoprene rubber?
Monomers ethylene glycol and terephthalic acid undergo condensation polymerization to give polymer called ___________
Write the name of one example of each polymer in which following repeating units.
\[\begin{array}{cc}
\ce{(-CF2-CF2-), -[NH-(CH2)5-CO] -, -(CH2-CH-), (-CH2-CH2-)}\\
\phantom{............................}|\\
\phantom{..............................}\ce{CN}
\end{array}\]
Write chemical reactions for the preparation of high-density polythene.
Explain the reactions involved in the preparation of viscose rayon.
The following structure represents the polymer:
\[\begin{array}{cc}
\ce{[-C-CH2-NH-C-(-CH2)5 NH -]_{{n}}}\\
\phantom{}||\phantom{.............}||\phantom{................}\\
\phantom{}\ce{O}\phantom{.............}\ce{O}\phantom{................}
\end{array}\]
Which of the following polymer is used in paints?
Identify additional polymers from the following.
I. \[\begin{array}{cc}
\ce{-(CH2 - CH -)_{{n}}}\\
\phantom{....}|\\
\phantom{.......}\ce{C6H5}
\end{array}\]
II. \[\ce{-(CH2 - CH = CH - CH2 -)_{{n}}}\]
III. \[\ce{-(CO(CH2)4 - CONH(CH2)6NH -)_{{n}}}\]
IV.
How many isoprene units are present in abscisic acid?
Identify the CORRECT statement regarding the following polymer.
\[\begin{array}{cc}
\phantom{....}\ce{O}\phantom{............}\ce{O}\phantom{...................}\ce{H}\phantom{.....}\\
\phantom{....}||\phantom{.............}||\phantom{...................}|\phantom{......}\\
\ce{-[C - (CH2)4 - C - NH - (CH2)6 - N -]_{{n}}}
\end{array}\]
Select the CORRECT match for both the polymers.
Which of the following polymers is obtained from chloroprene?
Novolac is obtained from ____________.
Which of the following catalysts is used in preparation of terylene?
Which among the following catalysts is used in the preparation of dacron?
Identify the catalyst used in the manufacture of high density polythene.
Which among the following monomers is used to prepare Teflon?
Which of the following monomers is used in the manufacture of Neoprene rubber?
Which among the following polymers is an example of addition polymer?
Which of the following polymers is used as insulation for cables?
Which among the following is an example of addition polymer?
Name the polymers used in laminated sheets and give the name of monomeric units involved in its formation.
Match the polymers given in Column I with their repeating units given in Column II.
| Column I | Column II |
| (i) Acrilan |
(a) \[\begin{array}{cc} |
| (ii) Polystyrene | (b) \[\begin{array}{cc} \ce{Cl}\phantom{.......}\\ |\phantom{........}\\ \phantom{}\ce{-(CH2 - C = CH - CH2)\underset{n}{-}} \end{array}\] |
| (iii) Neoprene | (c) \[\begin{array}{cc} \phantom{................................}\ce{CN}\\ \phantom{..............................}|\\ \ce{-(CH2 - CH = CH - CH2 - CH2 - CH)\underset{n}{-}} \end{array}\] |
| (iv) Novolac | (d) \[\begin{array}{cc} \ce{-(CH2 - CH)\underset{n}{-}}\\ \phantom{.....}|\\ \phantom{.......}\ce{CN} \end{array}\] |
| (v) Buna—N | (e)  |
| (f) \[\begin{array}{cc} \ce{-(CH2 - CH)\underset{n}{-}}\\ \phantom{.....}|\\ \phantom{......}\ce{Cl} \end{array}\] |
Which of the following products is formed when benzaldehyde is treated with CH3MgBr and the addition product so obtained is subjected to acid hydrolysis?
Polymer used in bullet proof glass is ______.
Which among the following polymers has high tensile strength and is used to obtain tyre cords?
Identify the monomer used to prepare neoprene.
Which of the following is a polymer of enzyme?
Name the compound which reacts with formaldehyde to produce ethyl alcohol.
Write the preparation of viscose rayon.
Write the name of the monomer of natural rubber.
Write the structure of isoprene and the polymer obtained from it.
Name and draw structure of the repeating unit in natural rubber.
Write the structure of isoprene and the polymer obtained from it.
Name and draw structure of the repeating unit in natural rubber.
Name and draw structure of the repeating unit in natural rubber.
Name and draw the structure of the repeating unit in natural rubber.
Name and draw structure of the repeating unit in natural rubber.
Write the structure of isoprene and the polymer obtained from it.
