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Polymers

(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Network polymers are thermosetting. Reason: Network polymers have high molecular mass.

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Option (i) is correct During polymerisation, extensive cross linking results in the creation of a three-dimensional network that is rigid, insoluble, and infusible.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement. Assertion: For making rubber synthetically, isoprene molecules are polymerised. Reason: Neoprene (a polymer of chloroprene) is a synthetic rubber.

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Option (v) is correct Natural rubber is made up of isoprene molecules, while neoprene, a synthetic rubber, is made up of chloroprene polymers.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Polyamides are best used as fibres because of high tensile strength. Reason: Strong intermolecular forces (like hydrogen bonding within polyamides) lead to close packing of chains and increase the crystalline character, hence, provide high tensile strength to polymers.

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Option (ii) is correct Polyamides, such as nylon, are the most often used fibres. Because of the strong intermolecular hydrogen connection, they have a high tensile strength.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Most of the Synthetic polymers are not biodegradable. Reason: Polymerisation process induces toxic character in organic molecules.

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Option (iv) is correct Enzymatic hydrolysis and environmental oxidation do not destroy the majority of synthetic polymers. Toxic characteristics are not produced via polymerization.

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Which of the following are characteristics of thermosetting polymers? (i) Heavily branched cross-linked polymers. (ii) Linear slightly branched long-chain molecules. (iii) Become infusible on moulding so cannot be reused. (iv) Soften on heating and harden on cooling, can be reused.

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Option (i) and (iii) are the answers. Thermosetting polymers have a lot of branching cross links. They can't be used again since they don't melt when heated and can't be remoulded.

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