Tag: chemistry

Questions Related to chemistry

STATEMENT-1 : PMMA (Polymethyl methacrylate) is used for making lenses and light covers.
STATEMENT-2 : It has excellent light transmission properties.

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. STATEMENT-1 is True, STATEMENT-2 is True, STATEMENT-2 is a correct explanation for STATEMENT-1

  2. STATEMENT-1 is True, STATEMENT-2 is True, STATEMENT-2 is NOT a correct explanation for STATEMENT-1

  3. STATEMENT-1 is True, STATEMENT-2 is False

  4. STATEMENT-1 is False, STATEMENT-2 is True

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Correct Option: A
Explanation:

PMMA (polymethyl methacrylate) is a widely commercially used bio-degradable polymer. It has excellent light transmission properties, due to which it is used for making lenses and light covers. 

List-l                         List-ll                                    
A)Rayon                   1)$CH _{2}O+C _{6}H _{5}OH$


B)Silicone polymers  2) $F _{2}C= CF _{2}$
 
                                             R
                                              |
C) Bakelite              3)  HO-Si-OH
                                              |
                                              R
D) Teflon                     4)Cellulose

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. A-4 B-3 C-1 D-2

  2. A- 1 B-3 C-2 D-4

  3. A-4 B-2 C-3 D-1

  4. A-2 B-4 C-3 D-1

Show answer
Correct Option: A
Explanation:

(A) Rayon:- Cellulose, organic polymer


(B) Silicone polymers consist of Si atom. Thus option 2.

(C) Bakelite:- condensation polymer formed by phenol and formaldehyde network structure


(D) Teflon:- Tetrafluoro ethene get polymerize forming teflon

A-4, B-3, C-1, D-2

A: Polymethyl methacrylate is also known as plexi glass.
R: PMMA is used in decorative articles.

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. Both A and R are correct and R is the correct explanation of the A

  2. Both A and R are correct but R is not the correct explanation of the A

  3. A is correct but R is in correct

  4. A is incorrect but R is correct

Show answer
Correct Option: B
Explanation:

Polymethyl methacrylate is also known as plexi glass.
PMMA is polymethyl methaacrylate. It is an addition hopolymer of methyl methacrylate ($\displaystyle CH _2 =C(CH _3)COOCH _3 $).
PMMA is used in decorative articles, lenses, sign borads and aircraft windows.

Which of the following fibres are made up of polyamides?

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. Wool

  2. natural silk

  3. Artifical silk

  4. Nylon

Show answer
Correct Option: A,B,D

List - I                                       List - II
A) Polystyrene                        p) Condensation polymer
B) Polythene                           q) Thermoplastic polymer
C) Nylon- $6, :6$                        r) Polyamide
D) Terylene                             s) Addition polymer

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. (a - q,s), (b - q,s), (c - p,q,r), (d - p)

  2. (a - p), (b - s), (c - p,r), (d - p,q)

  3. (a - s), (b - q), (c - p,r), (d - q)

  4. (a - q), (b - s), (c - r), (d - p,q)

Show answer
Correct Option: A
Explanation:
The addition polymers are formed by the repeated addition of monomer molecules possessing double or triple bonds, e.g., the formation of polythene from ethene and polypropene from propene. Addition polymers: Polyvinyl chloride, Polythene, Buna-S, Buna-N, etc.

Polystyrene  is a synthetic aromatic polymer made from the monomer styrene.
It is addition polymer as it is made of addition of monomers.

The condensation polymers are formed by repeated condensation reaction between two different bi-functional or tri-functional monomeric units. 

In these polymerisation reactions, the elimination of small molecules such as water, alcohol, hydrogen chloride, etc. take place. The examples are terylene (dacron), nylon 6, 6, nylon 6, etc. For example, nylon 6, 6 is formed by the condensation of hexamethylene diamine with adipic acid.


Hence, option A is correct.

List -I                                List -II
A) Polystyrene               p) $C _{6}H _{5}-CH=CH _{2}$
B) Buna-S                      q) $CH _{2}=CH-CH=CH _{2}$
C) Buna - N                    r) $CH _{2}OH-CH _{2}OH$
D) Terylene                    s) Condensation polymer

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. a- p

  2. b- p,q

  3. c-r

  4. d-r,s

Show answer
Correct Option: A,B,D
Explanation:

The condensation polymers are formed by repeated condensation reaction between two different bi-functional or tri-functional monomeric units. 

Terylene is a condensation polymer. Monomers of Terylene is ethylene glycol and teri-phthalic acid.
Buna-S is formed by the monomeric addition of compound styrene (p) and butadiene (q). 
Hence, options A, B and D are correct options.

Generally, polyamides are _____.

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. fiberes

  2. thermoplatics

  3. thermosetting

  4. elastomeres

Show answer
Correct Option: A
Explanation:

Polyamides are generally fibers because of the intermolecular forces like hydrogen bonding which gives them high tensile strength.

Non-stick frying pans are coated black with Teflon, a material that is resistant to heat. Teflon is a polymer of:

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. fluoromethane

  2. styrene

  3. ethylene

  4. tetrafluoroethylene

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Correct Option: D
Explanation:
Teflon is a polymer of tetrafluoroethylene $\left({C} _{2}{F} _{4} \right)$, also known as polytetrafluoroethylene. It is a manmade polymer that has particular applications in manufactured products because of the chemical properties of Polytetrafluoroethylene.

Plywood sheets are stuck together by unpolymerized:

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. nylon

  2. carbon black

  3. urea-formaldehyde resins

  4. styrene and butadiene

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Correct Option: C

Teflon, a polymer of tetrafluoroethylene, is an excellent plastic material for films and coatings. Which of the following is not the property of Teflon?

chemistry polymer polymers of commercial importance some commercially important polymers condensation polymers

  1. It is unaltered by radiation

  2. It can withstand high temperatures

  3. It is one of the most chemically-resistant plastic in the world

  4. It is an ideal insulator for high-frequency fittings

Show answer
Correct Option: A
Explanation:

$PTFE$ (Poly tetra fluoro ethylene) is very sensitive and is therefore not suitable for applications involving exposure of any radiation as it will degrade.