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Multiple choice distinction between pairs of amines organic compounds containing nitrogen organic compounds with functional group containing nitrogen chemistry

Primary, secondary and tertiary amines may be separated by using:

  1. iodoform

  2. diethyloxalate

  3. benzenesulphonyl chloride

  4. acetyl chloride
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The amine is treated with benzenesulphonyl chloride  and shaken with alkali solution when the three amine because in different way$.$

Primary amine from alkyl benzesulphoramide which dissolve in alkali to from sodium potassium salt of mono alkyl benzene sulphoramide$.$ Secondary amine from dialkali benzene$,$ in soluble in alkali solution and tertiary amines do not react with benzene sulphonyl chloride at all$.$

Multiple choice distinction between pairs of amines organic compounds containing nitrogen organic compounds with functional group containing nitrogen chemistry

Which of the following is not a property of diazonium salts?

  1. Diazonium salts are colourless crystalline solids.

  2. Being ionic in nature they are soluble in water.

  3. Most of these salts explode when dried.

  4. The aqueous solutions of these salts are poor conductors of electricity.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Salt solution such as sodium chloride ($NaCl$) conducts an electric current because it has ions in it that have the freedom to move about in solution. These ions are produced when sodium chloride dissolves in pure water to produce sodium ($Na^+$) and chloride ions ($Cl^–$).

Diazonium salts ($ArN _2^+X$) aqueous solutions are neutral to litmus and conduct electricity due to the presence of ions.
In an aqueous solution (that is, dissolved in water), the ions and electrons are much more mobile, thereby allowing electricity to flow through the solution.

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Teflon and Neoprene are the example of:

  1. copolymer

  2. monopolymer

  3. homopolymer

  4. condensation polymer.
Reveal answer Fill a bubble to check yourself
B,C Correct answer
Explanation

Teflon is homopolymer of monomeric units of tetra-fluoro-ethene

$CF _2=CF _2$
Neoprene is homopolymer of monomeric units of chloroprene [ $2-chloro-1,3-butadiene$].
so these are homopolymer and monomers, correct option is [B,C].

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Which of the following sets contain only addition homopolymers?

  1. Polythene, Natural rubber, Cellulose

  2. Nylon, Polyester, Melamine resin

  3. Teflon, Bakelite, Orlon

  4. Neoprene, PVC, Polythene
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation

On the basis of mode of polymerization, polymers can be classified into two types:-

[1] Addition polymer
[2] Condensation polymer
Addition polymers are formed by the repeated addition of monomer molecules possessing double or triple bonds. However, the addition polymers formed by the polymerization of a single monomeric species are known as homopolymers.
Example= Polythene: Made from the polymerization of ethene
Natural rubber: Made from the polymerization of cis-1,4-polyisoprene
Cellulose: Made from the polymerization of $\beta$ D- glucose
Neoprene: Made from the polymerization of chloroprene
PVC: Made from the polymerization of vinyl chloride

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

On complete hydrogenation, natural rubber produces:

  1. ethylene-propylene copolymer

  2. vulcanized rubber

  3. polypropylene

  4. polybutylene
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Natural rubber forms due to polymerisation of isoprene and on hydrogenation provide a polymer of the ethylene-propylene copolymer.


Hence, option A is correct.

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Polymerisation in which two or more chemically different monomers take part is called 

  1. addition polymerisation

  2. copolymerisation

  3. chain polymerisation

  4. homopolymerisation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Addition polymerisation - In this type of polymerisation, the molecules of the same monomer or different monomers add together on a large scale to form a polymer.
Copolymerisation - Copolymerisation is a polymerisation reaction in which a mixture of more than one monomeric species is allowed to polymerise to form a copolymer.
Chain polymerisation - Chain polymerisation or chain growth polymerisation is a polymerisation technique, where unsaturated monomer molecules add on to the active site on a growing polymerisation one at a time.
Homopolymerisation - Homopolymerisation is the polymerisation of a single type of monomer to form a homopolymer.

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Buna-S is a copolymer of:

  1. styrene and $1,\:3$ - butadiene

  2. styrene and ethylene
  3. $1,\:3$ - butadiene and ethylene
  4. $1,\: 3$ - butadiene and acrylonitrile
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Buna-S is formed from styrene and $1,:3$ - butadiene.
The reaction is shown below:
$nCH _2=CH-CH=CH _2 + nC _6H _5CH=CH _2 \rightarrow -(CH _2-CH=CH-CH _2-CH _2-CH(C _6H _5)) _n-$

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Which one of the following is an example of co-polymer ?

  1. Buna - S

  2. Teflon

  3. PVC

  4. Polypropylrnr
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Copolymer is a polymer made of two or more than two different monomers.

Buna-S is made of $1,3-$butadiene and styrene monomer.
But others are made of single polymer only.
Teflon $\longrightarrow$ Tetrafluorocarbon.
PVC $\longrightarrow$ Vinyl Chloride.
Polypropylene $\longrightarrow$ Propylene.

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Which of the following is not addition copolymer?

  1. Saran

  2. Vinyon

  3. SBR

  4. PVC
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

PVC (Polyvinyl chloride) is formed by the addition polymerization of a single monomer, vinyl chloride, making it a homopolymer rather than a copolymer. Saran, Vinyon, and SBR are copolymers formed from two or more different monomers.

Multiple choice copolymerisation types of polymerisation reactions polymer polymers chemistry

Which one is not a synthetic rubber?

  1. Buna -S

  2. Homopolymers of 1, 3-butadiene derivative

  3. PVC

  4. Copolymer of 1, 3-butadiene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

PVC is a thermoplastic polymer made from vinyl chloride monomer and is a plastic, not a synthetic rubber. Buna-S and copolymers/homopolymers of butadiene derivatives are classified as synthetic rubbers (elastomers).