Q.What are Macromolecules?
🔒You're viewing a preview — the full solution, concept, methods & PYQ mapping are locked.
🔒 Start your 14-day free trial to unlock the full solution →Concept understanding — Polymers and Monomers
Polymers are very large molecules (macromolecules) built by covalently linking together thousands of small, repeating units called monomers. The number of repeat units in a chain is called its degree of polymerisation.
- Monomer: the small reactive molecule that repeats to form the chain …
Ordinary small molecules like water or ethanol have modest molecular weights, but repeatedly linking many such small units together produces a completely different class of giant molecule with its own name and properties. …
Macromolecules are giant molecules of very high molar mass formed by the repeated joining of many small monomer units.
A macromolecule (literally 'large molecule') is a molecule of very high molecular mass, generally ranging from a few thousand up to several million. Such molecules are formed when a very large number of small, simple molecular units called monomers combine (polymerise) with one another.
Key features:
- Very high molecular mass and large size.
- Made of repeating structural units (the repeat unit derived from the monomer).
- May be natural or synthetic.
Examples:
- Synthetic: polythene, polyvinyl chloride (PVC), nylon, Bakelite. …
Showing the 12 most recent of 20 on this concept.
- CBSE 2024Set ANNUAL1 markMCQQ.What is the IUPAC name of isoprene monomer of natural rubber?(a) 3-Methyl-1,2-butadiene(b) 2-Methyl-1,3-butadiene(c) 1,3-Butadiene(d) 3-Methylbutadiene
›Reveal solutionSolution
Isoprene, CH2=C(CH3)-CH=CH2, is IUPAC-named 2-methyl-1,3-butadiene.
Isoprene is a 5-carbon diene: CH2=C(CH3)-CH=CH2. Numbering the longest chain containing both double bonds (buta-1,3-diene) from one end gives double bonds at C1-C2 and C3-C4, with a methyl substituent at C2. So its IUPAC name is 2-methyl-1,3-butadiene (also called 2-methylbuta-1,3-diene) …
- CBSE 2024Set ANNUAL1 markQ.What is the IUPAC name of the monomer unit of Polyacrylonitrile?
›Reveal solutionSolution
Polyacrylonitrile is an addition polymer of acrylonitrile, whose IUPAC name is prop-2-enenitrile.
Polyacrylonitrile (used to make fibres like Orlon/PAN, and as a precursor in carbon-fibre manufacture) is formed by addition polymerisation of its monomer, CH2=CH-CN, commonly called acrylonitrile. Naming it by IUPAC rules: the longest chain including the nitrile group is a 3-carbon chain (propene skele …
- CBSE 2023Set ANNUAL1 markMCQQ.The monomer of Nylon-6 is -(a) Ethylene(b) Propene(c) Styrene(d) Caprolactum
›Reveal solutionSolution
Nylon-6 is made by the ring-opening polymerisation of caprolactam.
Nylon-6 is obtained by heating caprolactam (a cyclic amide, 6-aminohexanoic acid lactam) with water, which opens the ring to give an amino acid that then undergoes self-condensation (polymerisation) to give Nylon-6, a polyamide. Ethylene, propene and styrene ar …
- CBSE 2023Set ANNUAL1 markMCQQ.Caprolactum is monomer of(a) Nylon 6(b) Nylon 6, 6(c) Bakelite(d) Terylene
›Reveal solutionSolution
Caprolactam, a cyclic amide, opens and polymerises on heating to give the polyamide Nylon 6.
Caprolactam (a 6-membered cyclic amide) is heated in the presence of water, which opens the ring; the resulting amino-acid units then undergo condensation polymerisation with each other, forming the linear polyamide Nylon 6. (Nylon 6,6 is instead made from hex …
- CBSE 2022Set HE2181 markQ.Fill in the blank: Teflon is a polymer of ______.
›Reveal solutionSolution
Teflon (polytetrafluoroethylene, PTFE) is made by free-radical addition polymerisation of tetrafluoroethene, CF2=CF2.
Tetrafluoroethene is polymerised under high pressure using a peroxide (or persulphate) catalyst:
n CF2=CF2 -(catalyst, high pressure)-> [-CF2-CF2-]n (Teflon) …
- CBSE 2022Set HE2181 markQ.Answer in one word/sentence: Write the monomer of polythene.
›Reveal solutionSolution
Polythene is formed by free-radical addition polymerisation of the simple alkene monomer ethene (ethylene), CH2=CH2.
Under high pressure (~1000-2000 atm) and temperature, with a trace of peroxide catalyst, thousands of ethene molecules add on to each other, the pi-bond of each monomer opening up to form new sigma bonds to the growing chain:
n CH2=CH2 -(catalyst, high P & T)-> [-CH2-CH2-]n (low-density polythene) …
- CBSE 2022Set TERM21 markMCQQ.The monomer of natural rubber is:(a) Isoprene(b) Chloroprene(c) Phenol(d) None of these
›Reveal solutionSolution
Natural rubber is a polymer of isoprene (2-methyl-1,3-butadiene) units joined in a cis configuration.
Natural rubber is cis-1,4-polyisoprene: it is obtained by the polymerisation of the monomer isoprene (CH2=C(CH3)−CH=CH2, 2-methylbuta-1,3-diene). The isoprene units link head-to-tail with all double bonds in the cis configuration, which gives natural rubber its characteristic elasticity (the cis arrangement prevents the polymer chains from p …
- CBSE 2022Set TERM21 markQ.Draw the structure of Nylon 6,6.
›Reveal solutionSolution
Nylon 6,6 is a polyamide made by condensing hexamethylenediamine (6 carbons) with adipic acid (6 carbons), losing water at each amide linkage.
Nylon 6,6 is formed by heating hexamethylenediamine [H2N−(CH2)6−NH2] with adipic acid [HOOC−(CH2)4−COOH] under high pressure and temperature. This is a step-growth (condensation) polymerisation: the -NH2 of the diamine reacts with the -COOH of the diacid, releasing water at each step and building alternating amide (peptide-type) linkages along the chain. The name '6,6' records that both monomers contribute 6 carbon atoms each.
Repeat unit / structure:
…
- CBSE 2022Set ANNUAL1 markQ.Identify the monomer of the polymer represented as (−CH2−CHCl−)n.
›Reveal solutionSolution
PVC is the addition polymer of vinyl chloride; reversing the addition-polymerisation pattern gives back the monomer, chloroethene.
The repeat unit −CH2−CHCl− is formed by opening the C=C double bond of a vinyl-type monomer and joining the units head-to-tail. Working backwards, the monomer must be:
CH2=CHCl (vinyl chloride / chloroethene)
…
- CBSE 2020Set HE8221 markQ.Write True or False: Formation of terylene is by reaction between Ethylene Glycol and Terphthalic acid.
›Reveal solutionSolution
Terylene is a polyester made by step-growth (condensation) polymerisation between a diol (ethylene glycol) and a dicarboxylic acid (terephthalic acid), with loss of water at each ester linkage.
The statement is True.
Terylene (also called Dacron or PET, polyethylene terephthalate) is a synthetic polyester fibre prepared by heating a mixture of ethylene glycol [HOCH2CH2OH] and terephthalic acid [HOOC–C6H4–COOH] in the presence of a catalyst (e.g. zinc acetate/antimony trioxide) at high temperature:
…
- CBSE 2020Set ANNUAL1 markQ.Which polymer is prepared by the monomer, styrene?
›Reveal solutionSolution
Styrene is an alkene bearing a phenyl group; its free-radical addition polymerisation links many styrene units end-to-end through their C=C bonds to give polystyrene.
Styrene, C6H5-CH=CH2 (vinylbenzene), undergoes addition polymerisation (typically free-radical initiated) in which the C=C double bond of each monomer opens up and links to the next, forming a long saturated carbon backbone with a phenyl group pendant on every alternate carbon:
…
- CBSE 2020Set ANNUAL1 markMCQQ.Caprolactam is monomer unit of:(a) Dacron(b) Nylon 6(c) Teflon(d) Buna-N
›Reveal solutionSolution
Caprolactam undergoes ring-opening self-condensation on heating with water to give Nylon 6.
Caprolactam is a six-membered cyclic amide (lactam). On heating in the presence of a trace of water at high temperature, its ring opens and the resulting molecules undergo self-condensation (polymerisation), linking up via amide bonds to form a linear polyamide — Nylon 6 (named for the six carbons in the repeating unit). This is distinct from Nylon 6,6, which is instead made by condensing two different monomers (hexamethylenediamine and adipic acid).
…
🎓Unlock everything free for 14 days
- ✓Full step-by-step solutions
- ✓Concept-first explanations
- ✓Methods, shortcuts & mistakes
- ✓PYQ mapping + timed mock tests
Full access for 14 days. No credit card required.