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Polymers and biomolecules — Question 74

Original QCE Vault practice · 4 marks

Q74 · Practice questionSimple familiar4 marks

QUESTION 74 (4 marks)

Two polypropene samples have identical chain lengths. In X, methyl groups follow a regular isotactic arrangement. In Y, they follow an irregular atactic arrangement.

a) Explain which sample is likely to pack more regularly and be more crystalline. [2 marks]

b) Predict which sample generally has greater stiffness, with a reason. [2 marks]

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