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NCERT Exemplar Class 12 Chemistry Chapter 15 Solutions: Polymers

NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 will help you to get a deeper knowledge about Polymers. To give you an idea, this chapter of NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers covers all aspects of the chapter such as Polymers and their Classifications, Types of Polymerization Reactions, Molecular Mass of Polymers, Biodegradable Polymers, Polymers of Commercial Importance.

NCERT exemplar solution will also help you to understand Synthetic Polymers, Polymers of glucose stored in animals, commercial name of polyacrylonitrile, the structure of Polymers, and ethylene glycol as monomers and low-density polythene. NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers has a total of 55 questions that are divided into 5 sections touching all the topics based on Chapter 15. The questions are of various kinds which will help you get a complete revision with the help of MCQ’S, short answer questions, fill in the blanks, true or false, numerical questions, worksheets and exercises.

We have created solutions to various NCERT exemplar solutions in unique and simple steps so that you can learn easily without any hurdle. By following the strategies of the professionals at Instasolv, you may enhance your marks in CBSE Board exams.

Important Topics for NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers

  1. Polymers are derived from monomers, which are composed of repeating structural units of high molecular weight macromolecules. They can be in natural or synthetic form and are classified in different ways, for example depending on the origin, structure, etc.
  2. Classification of Polymers: Polymers cannot be classified in any one category due to their complex structure, different behaviours and wide applications.
  • Polymer Classification based on Source of Availability:
  1. Natural Polymers: They occur naturally and are found in plants and animals. For example, protein, starch, cellulose, rubber.
  2. Semi-synthetic Polymers: They are made of naturally occurring Polymers and undergo further chemical modification. For example, cellulose nitrate, cellulose acetate. 
  3. Synthetic Polymers: These are man-made Polymers. Plastic is the most common and widely used synthetic polymer. It is used in industries and various dairy products. For example, nylon-6, 6, polyether, etc.

 

  • Polymer Classification based on the Structure of the Monomer Chain

 

  • Linear Polymers:

 

 

   Long, linear Polymers fall into this category. PVC, or polyvinyl chloride, is most commonly used in the manufacture of pipes, and electrical cables are an example of a linear polymer.

 

  • Branched-chain Polymers:

 

When Polymers form linear chains of polymer branches, such Polymers are called branch chains. For example, low-density polythene.

 

  • Cross-linked Polymers:

 

They consist of bifunctional and trifunctional monomers. They have a stronger covalent bond than other linear Polymers. Bakelite and melamine are examples in this category. Other Ways to Classify Polymers

 

  • Polymer Classification based 0n Polymerization

 

  1. Addition Polymerization:  poly ethane, Teflon, Polyvinyl chloride (PVC)
  2. Condensation Polymerization:  Nylon -6, 6, perylene, polyesters.

 

  • Polymer Classification based Monomers:

 

  1. Homomers: In this type, there is only one type of monomer unit. For example, polyethene 
  2. Heteropolymer or copolymer: composed of different types of monomer units. For example, nylon-6,6

 

  • Polymer Classification Based on Molecular Forces:

 

  1. Elastomers: they are rubber-like solids with weak conductivity. For example, rubber. 
  2. Iberian fibres: strong, rigid, with high tensile strength and strong interaction forces. For example, nylon-6, 6. 
  3. Thermoplastics: they have intermediate attractive forces. For example, polyvinyl chloride. 
  4. Thermosetting Polymers: These Polymers greatly improve the mechanical properties of the material. For example, phenolics, epoxies, and silicones.

 

  • Polymer structures:

 

Most Polymers around us are made up of a hydrocarbon skeleton. A hydrocarbon skeleton is a long chain of linked carbon and hydrogen atoms that is possible due to the tetravalent nature of carbon. Examples are polypropylene, polybutylene, polystyrene.

 

  • Polymers are of Different types

 

Based on the backbone chain, Polymers can be divided into:

  1. Organic Polymers: Carbon skeleton.
  2. Inorganic Polymers: It is constituted by other elements irrespective of carbon.
  3. Synthetic Polymers: They are man-made Polymers. One of the simplest Polymers is Polyethylene that has ethene or ethylene as monomers. A linear polymer is known as the high-density polyethylene-HDPE
  • Various types of Synthetic Polymers:

 

  • Nylon- Nylon belongs to the family of synthetic Polymers and is also known as polyamide. Nylon is a widely used polymer. The backbone, known as amide, makes it hydrophilic compared to other Polymers. Nylon combines hydrogen with water.
  • Polyvinyl Chloride

Polyvinyl chloride or PVC is the third-largest plastic produced after polypropylene and polyethene. This PVC is used for construction purposes because it is known to be stronger and cheaper than other alternatives such as copper or iron.

 

  • Low-Density Polyethylene–

 

Low-density polymer Polymers are common types of synthetic Polymers that are widely used in daily life. LDPE is a type of thermoplastic 

 

  • Polypropylene–

 

Polypropylene also called Polypropene, also known as polypropylene, is a type of thermoplastic synthetic polymer that is used in a variety of applications, including packaging, labels, stationery, and textiles.

  • Synthetic Polymer Uses:
  1. Polymer called polyethene is used in plastic bags and film packaging.
  2.  Polyethene is used in bottles, electrical insulation, toys, etc. 
  3. Synthetic polymer polystyrene is used in cabinets and packaging.
  4. Polyvinyl acetate is used in adhesives and latex paints.

 

  1. Based on their synthesis:

 

  • Natural Polymers

 

  • Synthetic Polymers

 

 

 

  • Biodegradable Polymers:

 

The Polymers that are prone to decay by microorganisms such as bacteria are known as biodegradable Polymers. 

 

  • High-Temperature Polymers:

 

This polymer is stable at high temperatures. Due to their high molecular weight, these do not disappear even at high temperatures.

  • Few of the important Polymers are:
  • Polypropylene: Polypropylene: it is a type of polymer that softens beyond a specific temperature, which allows it to mould and solidifies on cooling.
  • b. Polyethene: This is the most common type of plastic around us. Mainly used for packaging from plastic bags to plastic bottles. General formula =(C2H4) n.
  • Properties of Polymers:
  • Physical Properties
  • As the chain length and crosslinking increase, the polymer’s tensile strength increases.
  • Polymers do not melt, they change the state from crystalline to semi-crystalline.

 

  • Chemical Properties:

 

  • Dipole-dipole binding side chains give Polymers great flexibility.
  • Polymers with linked Van der Waals forces are known to be weak, but the melting point of the polymer is lower.
  • Optical Properties:

PMMA and HEMA: They are used for spectroscopy and analytical lasers due to their ability to change the refractive index with temperature, as in the case of MMA.

  • Types of Polymerization Reactions:
  • Addition Polymerization

Popularly known as Chain polymerization. In this case, the smaller monomer units are combined into a larger polymer. For example, polymerization of ethane in the presence of peroxide

b.Condensation Polymerization

During polymerization, small molecules such as H2O, CO, and NH3 are removed. For example, making nylon-6, 6.

  • Molecular Mass calculation of Polymers?
  • Number Average Molecular Masses
  • Weight Average Molecular Mass

Use of polymer:

  • Polypropylene is used in various industries such as textiles, packaging, stationery, plastics, etc.
  • Polystyrene is one of the most used plastics in the packaging industry. 
  • The main use of polyvinyl chloride is in the manufacture of sewage pipes.
  • Polyvinyl chloride is used in clothing and furniture. It is also used in vinyl flooring. 
  • Used for the manufacture of paints, coatings, and varnishes. 
  •  Bakelite is used to manufacture electrical switches, kitchen products, toys, etc. 

Discussion of Exercises NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers

 

  • The 1st section of NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers have 19 questions which are MCQs that will ask you to choose correct statements based on semi-synthetic Polymers, polymer properties, and its structures.

 

    1. The 2nd section has 17 questions which are short answer type questions that will help you to understand additional polymerization of alkenes and structural differences between HDP and LDP.
    2. The 3rd section has questions which are matching type questions that the mixture of different terminologies 7 based on that will ask you to match different Polymers with their respective structures and formulas.
    1. The 4th section has 7 questions which are Assertion and Reason Type questions that are based on synthetic Polymers, the tensile strength of polyamides, olefin monomers, etc.
    1. The 5th section has 5 questions that are a long answer type which will ask you to support your answers with basic concepts of structures similarities in Polymers, the difference between low and high-density Polymers and intermolecular forces between rubber and plastics.
    1. The NCERT exemplar questions include the simplest quality problems that will test you in varying levels of difficulty on any given topic. Questions that are mentioned within the NCERT exemplar are of immense importance from CBSE’s point of view.

Why Use NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers by Instasolv?

NCERT Exemplar Class 12 Chemistry Solutions Chapter 15 – Polymers by Instasolv expert incorporates all the significant subjects with point by point explanation that plans to assist students with understanding the ideas better. Experiencing the arrangements given on this page will assist you in knowing how to approach and take care of the issues.