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Multiple choice types of polymerisation reactions condensation polymerisation polymer polymers chemistry

Hair sprays generally contain resins in a volatile solvent. Upon drying, they leave a thin film that holds the hair in place. Which of the following is a resin used in hair spray?

  1. Polyester

  2. Polyvinyl alcohol

  3. Polyvinyl pyrrolidone (PVP)

  4. Polythene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
$PVP$ (Polyvinyl pyrrolidone) is a versatile ingredient which is used in cosmetics and beauty industry as a bindes, film former, emulsion stabilizer, suspending agent and hair fixative used in products like mascara, eyeliner, hair conditioners, hair sprays and shampoos.
Multiple choice types of polymerisation reactions condensation polymerisation polymer polymers chemistry

Which of the following polymers can be made by condensation polymerisation reaction?

  1. Dacron
  2. Nylon - $6,\: 6$

  3. Bakelite

  4. Polyethylene
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

Condensation polymers are formed by repeated condensation reactions 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. takes place. 

Dacron, Nylon-6.6 and Bakelite are produced by condensation polymerisation.

On the other hand, Polyethylene is formed by breakage of the double bond and there is no elimination of molecules.


Multiple choice types of polymerisation reactions condensation polymerisation polymer polymers chemistry

Which of the following is/are not a condensation copolymer?

  1. Nylon-$6$
  2. Nylon-$6,6$

  3. Dacron

  4. PVC
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation
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, etc. For example, nylon 6, 6 is formed by the condensation of hexamethylenediamine with adipic acid.

When two different types of monomers are joined in the same polymer chain, the polymer is called a copolymer. 
Nylon 6 is a condensation polymer but it's not a co-polymer.
PVC is an addition polymer.

Hence, options A and D are correct.
Multiple choice types of polymerisation reactions condensation polymerisation polymer polymers chemistry

Nylon-$6$ is prepared by linear condensation homopolymerization reaction of: 

  1. caprolactum

  2. hexamethylene diamine and adipic acid
  3. $6$-aminohexanoic acid

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

Solution:- (A) Caprolactam

Nylon-$6$ is prepared by linear condensation homopolymerization reaction of caprolactam.
$n \left( \text{Caprolactum} \right) \xrightarrow[{N} _{2}]{533 \; K} \text{Nylon}-6$

Multiple choice water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

Which is a green house gas?
A) Methane 

B) Chlorofluorocarbons 
C) $CO _{2}$

  1. $A$ and $B$
  2. $B$ and $C$
  3. $C$ and $D$
  4. $A, B$ and $C$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Greenhouse effect
* The progressive heating up of surface of the earth is earth is called green house effect or global warming.
 $CO _2$ and $H _2O$ block a part of the heat (IR) emitted by the earth & reflect back. Due to this earth surface gets heated up.
 50% in $CO _2$ content of air can increase the surface temperature of the earth by $3^oC$.
* In addition to $CO _2$ , the other green - house gases are CFCs (17%), $O _3$ (18%), NO (4%), water vapour (2%).

Multiple choice water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

Which of the following is not a sink for CO?

  1. Haemoglobin

  2. Microorganims present in the soil

  3. Oceans

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation


* Incomplete combustion of fossil fuels liberate CO into air. 80% of CO is released from automobiles.


* Permissible level of CO in air is 9 ppm. It reduces $O _2$ supply in human by forming a stable carboxyhaemoglobin.

$2C+O _2\rightarrow 2CO$
$2CH _4+3O _2\rightarrow 2CO+4H _2O$

* CO interacts with oxyhaemoglobin ($O _2Hb$) and forms carboxyhaemoglobin (CO-Hb) as :

$O _2Hb+CO\rightarrow COHb+O _2$

* CO has high affinity for haemoglobin than that of oxygen.

Therefore, option A is correct.