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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
Write any ‘two’ uses of terylene.
Explain the following term: Homopolymers
Bakelite is the polymer of:
(a) Benzaldchyde and phenol
(b) Acetaldehyde and phenol
(c) Formaldehyde and phenol
(d) Formaldehyde and benzyl alcohol
Write the formulae of the raw materials used for preparation of Dextran.
The Zieglar-Natta catalyst is used in the preparation of _______.
(A) LDPE
(B) PHBV
(C) PAN
(D) HDPE
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Answer the following in one sentence.
Identify 'A' in the following reaction:
Answer the following in one sentence.
Identify 'B' in the following reaction:
\[\ce{H2N -(CH2)6 - NH2 + HOOC - (CH2)4 - COOH ->[N2][533 K]}\]'B'
Answer the following in one sentence.
What type of intermolecular force leads to high-density polymer?
Answer the following in one sentence.
Identify thermoplastic and thermosetting plastic from the following:
- PET
- Urea formaldehyde resin
- Polythene
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Answer the following.
Write the reaction of the formation of Nylon 6.
Answer the following.
Draw the structures of polymers formed from the following monomers
H2N–(CH2)5 – COOH
Answer the following.
Write name and formula of raw material from which bakelite is made.
Identify condensation polymers and addition polymers from the following.
-(CH2 - CH = CH - CH2 -)n
Attempt the following:
Explain the vulcanisation of rubber. Which vulcanizing agents are used for the following synthetic rubber?
a. Neoprene
b. Buna-N
Attempt the following:
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write the structure of the monomer used in natural rubber.
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\[\begin{array}{cc}
\ce{(-CF2-CF2-), -[NH-(CH2)5-CO] -, -(CH2-CH-), (-CH2-CH2-)}\\
\phantom{............................}|\\
\phantom{..............................}\ce{CN}
\end{array}\]
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Select the CORRECT match for both the polymers.
\[\ce{{n} CH2 = CH2 ->[333 K - 343 K][6 - 7 atm, catalyst] X}\]
Which of the following is CORRECT about polymer 'X'?
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Which of the following products is formed when benzaldehyde is treated with CH3MgBr and the addition product so obtained is subjected to acid hydrolysis?
F2C = CF2 is monomer of the polymer -
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Identify the monomer used to prepare neoprene.
Which of the foolowing polymer is used in the manufacture of insulators.
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Answer the following.
Name and draw structure of the repeating unit in natural rubber.
Answer the following.
Write the structure of isoprene and the polymer obtained from it.
Write the structure of isoprene and the polymer obtained from it.
Name the compound which reacts with formaldehyde to produce ethyl alcohol.
Name and draw structure of the repeating unit in natural rubber.
Write the name of the monomer of natural rubber.
Another name of terylene is ______.
Name and draw structure of the repeating unit in natural rubber.
Match the following pairs:
| Polymer | Monomer | ||
| (i) | Teflon | (a) | CH2 = CH2 |
| (ii) | PVC | (b) | CF2 = CF2 |
| (iii) | Natural rubber | (c) | Isoprene |
| (iv) | Polythene | (d) | H2C=CHCl |
The monomer used in preparation of teflon is ______.
Write the structure of isoprene and the polymer obtained from it.
Write the structure of isoprene and the polymer obtained from it.
Name and draw structure of the repeating unit in natural rubber.
Which from following statements is NOT true regarding neoprene?
