Question map
With reference to polyethylene terephthalate, the use of which is so widespread in our daily lives, consider the following statements : 1. Its fibres can be blended with wool and cotton fibres to reinforce their properties. 2. Containers made of it can be used to store any alcoholic beverage. 3. Bottles made of it can be recycled into other products. 4. Articles made of it can be easily disposed of by incineration without causing greenhouse gas emissions. Which of the statements given above are correct ?
Explanation
The correct answer is Option 1 (1 and 3). Polyethylene terephthalate (PET) is a versatile polymer with significant industrial applications.
- Statement 1 is correct: PET fibres are commonly blended with natural fibres like cotton (to create polycot) and wool (to create polywool). This blending enhances the durability, wrinkle resistance, and tear strength of the natural fibres.
- Statement 3 is correct: PET is 100% recyclable. Used bottles are crushed and processed into "flakes," which are then recycled into new containers, polyester fibres for carpets, or even clothing.
Why other statements are incorrect:
- Statement 2: PET is generally unsuitable for long-term storage of high-concentration alcoholic beverages because alcohol can act as a solvent, potentially causing the leaching of chemicals like acetaldehyde and antimony into the drink.
- Statement 4: Incineration of PET releases greenhouse gases like Carbon Dioxide (CO2) and can emit toxic gases if not controlled, contradicting the claim that it causes no emissions.
PROVENANCE & STUDY PATTERN
Full viewThis is a classic 'Applied Science' question where common sense outweighs rote learning. While Statement 1 and 3 are general observations (polycotton shirts, recycling bins), Statements 2 and 4 are 'Science Traps' designed to test your grasp of extreme absolutes ('any' alcohol, 'without' emissions). The strategy here is not to know PET chemistry, but to spot the violation of basic environmental laws.
This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.
- Statement 1: Can polyethylene terephthalate (PET) fibers be blended with wool and cotton fibers to enhance or reinforce their properties?
- Statement 2: Are polyethylene terephthalate (PET) containers suitable and approved for storing all types of alcoholic beverages?
- Statement 3: Can polyethylene terephthalate (PET) bottles be recycled and converted into other products?
- Statement 4: Can polyethylene terephthalate (PET) articles be safely incinerated without producing greenhouse gas emissions?
Lists synthetic fibres (e.g., dacron, teteron, terylene) alongside natural fibres in textile manufacture, showing synthetics are already integrated into textile production.
A student could note PET is a common polyester (like dacron/terylene) and so infer that similar production/usage practices might allow blending with cotton/wool to modify properties.
States cotton 'competes with' wool, silk, rayon, nylon and synthetic fibres, implying synthetic fibres are alternatives/co-used in the textile market.
Using basic knowledge that competition often leads to blends/variants, a student could investigate whether cotton products are blended with synthetics to gain desired traits (e.g., strength, wrinkle resistance).
Describes wool's key properties (insulation, moisture absorption, durability), which are specific attributes manufacturers might want to retain or modify by blending.
A student could consider which wool properties to enhance or protect (e.g., increase strength or wrinkle resistance) and whether adding a polyester like PET could plausibly provide those effects.
Notes mechanization of textile manufacture and broad use of fibers, indicating production processes exist that can handle large-scale fibre processing and mixing.
A student might infer that industrial spinning/weaving equipment can blend different fibre types (natural + synthetic) and so check technical sources on blending methods for PET with cotton/wool.
Ethanol is described as a good solvent and is soluble in water, indicating alcoholic liquids can interact chemically with container materials.
A student could use this to check PET's chemical resistance to ethanol (especially at different strengths) to judge suitability for storing various alcoholic beverages.
Provides a classification of plastics for packaging (rigid, flexible, multi-layered), implying different plastic structures are used for different packaging needs.
A student could identify which package category PET bottles fall into and whether single-layer PET is appropriate for highβalcohol products or if multi-layer/alternative materials are recommended.
Lists regulatory prohibitions on certain single-use plastic items, showing that legal/regulatory rules govern plastic use and disposal.
A student could look up relevant food-contact or beverage-specific regulations to see approvals/restrictions for PET use with alcoholic beverages.
Notes widespread use of plastics for packaging because of cost and convenience, but also highlights environmental concerns and 'throw away' culture.
A student could weigh practical/common use of PET for drinks against concerns (e.g., reuse, leaching over time) to assess whether PET is commonly used or recommended for all beverage types.
- Explicitly lists recycling of bottles and plastics as an action to be taken.
- Groups bottles with other recyclables (newspapers, cans, glass), implying routine recycling practice for plastics.
- Recommends recycling bottles and plastics as standard waste-management behaviour.
- Pairs the advice with buying refillable and recyclable products, implying closedβloop or reuse practices.
- Directs learners to find out how plastics are recycled, implying an established recycling process exists.
- Asks about environmental impacts of the recycling process, linking recycling practice to downstream product or process considerations.
- Directly compares thermal recovery (burning) of plastics with recycling and states recycling is more environmentally friendly, implying burning produces emissions.
- Specifically names 'burning plastic with power recovery' as thermal recovery, linking incineration to an inferior GHG outcome.
- Lists 'in waste combustion' as a pathway associated with waste impacts, indicating combustion (incineration) is connected to greenhouse gas considerations.
- States indirect greenhouse gas emissions are connected to waste management activities, reinforcing that incineration contributes to GHG emissions.
- Shows plastics already contribute substantial GHG emissions across their lifecycle, indicating waste-treatment choices (like incineration) affect overall emissions.
- Notes the majority of plastics' lifecycle emissions come from production/conversion, but implies waste management (including combustion) is part of the lifecycle GHG picture.
Defines incineration as burning waste at high temperature and states burning garbage produces toxic ash and air pollution.
A student could extend this by noting that burning organic or carbon-containing materials (like plastics) typically produces combustion products and so would check whether PET combustion yields CO2 or other gases.
States that waste-to-energy can divert waste and 'generate clean power without the emission of harmful greenhouse gases' and contrasts incineration with emerging technologies like pyrolysis and gasification.
One could treat this as a rule that some waste-to-energy routes claim lower GHG outputs and therefore compare standard incineration of PET with alternative processes (pyrolysis/gasification) to see if PET combustion emits GHGs.
Lists disposal methods and explicitly mentions pyrolysis β 'a process of combustion in the absence of oxygen.'
A student could investigate whether PET under pyrolysis (oxygen-limited) produces different gaseous products (less CO2, more hydrocarbons or monomers) than open incineration.
Gives a general pattern that greenhouse-gas emissions can be by-products or losses in industrial processes.
Apply this pattern to PET incineration by checking whether combustion of polymer feedstocks typically produces greenhouse gases as by-products.
Defines 'net zero' as produced greenhouse gas equalling removed greenhouse gas, highlighting that emissions can be balanced or offset.
A student could use this to distinguish whether 'no greenhouse gas emissions' means zero direct emissions from incineration or could be achieved via offsets/capture after incinerating PET.
- [THE VERDICT]: Logical Trap. Statements 1 and 3 are Sitters (General Observation). Statements 2 and 4 are Traps (Extreme Qualifiers). Solvable via elimination.
- [THE CONCEPTUAL TRIGGER]: 'Chemistry in Everyday Life' (NCERT Class 12) merged with 'Solid Waste Management' (Environment).
- [THE HORIZONTAL EXPANSION]: Memorize these Polymer Siblings: 1. Thermoplastics (PET, PVC, Polystyrene) -> Recyclable. 2. Thermosetting (Bakelite, Melamine) -> Non-recyclable/Heat resistant. 3. Additives: BPA (Bisphenol A) in Polycarbonates (Endocrine disruptor). 4. Bioplastics: PLA (Polylactic Acid) vs PHA (Polyhydroxyalkanoates).
- [THE STRATEGIC METACOGNITION]: Do not memorize the specific chemical resistance of every plastic. Instead, adopt the 'No Free Lunch' heuristic: No material is perfect for *all* uses (Statement 2), and no combustion process is free of emissions (Statement 4). If it sounds too good to be true, it's wrong.
Textile fibres are classified into natural (cotton, wool) and synthetic (polyester, nylon), a basic distinction relevant to questions about combining or substituting fibres.
High-yield for UPSC because questions often ask about industrial raw materials, textile sector composition and comparative advantages of fibre types; links to industry, agriculture and manufacturing topics and enables answering questions on material selection, import dependence and textile policy.
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 26: Agriculture > General > p. 257
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 26: Agriculture > Generrl > p. 258
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 28: Manufacturing Industry and The Iron and Steel Industry > Groups of Industries > p. 279
Wool provides insulation, moisture absorption, wrinkle resistance and durabilityβkey characteristics considered when evaluating blends or performance enhancements.
Useful for answering questions on suitability of fibres for different climates, garment uses and value addition in textile products; connects to topics on regional specialisation of wool production and downstream industries.
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 26: Agriculture > Generrl > p. 258
Polyester variants such as Dacron and Terylene are established synthetic fibres in textile manufacture and are relevant when discussing polyester's role in the textile mix.
Important for questions on synthetic fibre technology, textile modernization and substitution effects; helps in understanding policy/industrial shifts toward synthetic fibre production and its implications for cotton/wool sectors.
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 28: Manufacturing Industry and The Iron and Steel Industry > Groups of Industries > p. 279
Ethanol is a strong solvent, fully miscible with water, and is the active ingredient in alcoholic beverages β properties that determine how container materials interact with the liquid.
Understanding ethanol's solvent behaviour is high-yield for judging material compatibility and safety of packaging for beverages and pharmaceuticals; it connects chemistry fundamentals to applied questions on storage, contamination risk, and health implications.
- Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > 4.4.1 Properties of Ethanol > p. 72
- Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > Activity 4.8 > p. 73
Plastics are classified into rigid, flexible and multi-layer packaging categories, which affect their performance and suitability for different liquid products.
Mastering plastic classification helps answer regulatory and technical questions about which polymer forms are appropriate for food and beverage packaging, links to manufacturing and waste-management policy, and aids in evaluating compliance/approval issues.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > Amendment rules eozz > p. 99
Regulatory bans and restrictions on certain single-use plastics influence which plastic containers may be allowed or discouraged for consumer products.
Knowledge of plastic bans and environmental concerns is important for policy-oriented UPSC questions on waste management, packaging regulation, and sustainable alternatives; it ties environmental governance to industrial and consumer regulation.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > 5.2.4 Plastic Waste Management Amendment Rules, zozo. > p. 98
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > 5.1o.r. Plastic Waste > p. 84
Recycling of bottles and plastics is the central practice relevant to whether PET bottles can be processed for reuse.
High-yield for UPSC environment/waste-management questions: explains a basic waste-management option and links to policy measures. Connects to circular economy, solid-waste management, and consumer-behaviour topics, enabling answers on practical recycling measures and policy recommendations.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 17: Contemporary Issues > Recycling and Waste Reduction > p. 91
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 6: Environmental Degradation and Management > E. Recycling and Waste > p. 31
Microplastics from Textiles. Since PET fibers are blended with cotton (Statement 1), the next logical question is on 'Microfiber shedding' during washing as a primary source of marine microplastics. Also, look out for 'Extended Producer Responsibility (EPR)' which specifically targets PET bottle waste.
Apply the 'Thermodynamics of Absolutes'. Statement 4 claims incineration causes 'no greenhouse gas emissions'. PET is a hydrocarbon (petroleum-based). Burning carbon *must* produce CO2. This violates the Law of Conservation of Mass. Eliminate 4. Statement 2 says 'any' alcoholic beverage. Alcohol is a solvent; strong solvents dissolve plastics. 'Any' is a red flag. Eliminate 2. Answer is A.
Link this to GS-3 Environment (Plastic Waste Management Rules 2021). The ban on Single-Use Plastics (SUP) targets items with 'low utility and high littering potential' (straws, stirrers), but exempts PET bottles (high utility, recyclable). This explains why PET is regulated differently than PVC banners.