Indian Forest Service (Mains), Chemistry optional · 2021 · Paper II
Q6(b)(ii). End-group content of polystyrene
Question
Calculate the weight fraction of phenyl end groups in polystyrene of molar mass 150000 g mol⁻¹ if both ends of an average molecule are phenyl groups.
Answer in brief
The end-group weight fraction is approximately 1.027 × 10⁻³, or 0.1027%.
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Coversend-group analysispolystyreneweight fractionnumber-average molar mass
All parts of Question 6
- 6(a)(i) Malonic ester ring synthesis5 marks
- 6(a)(ii) Wittig olefination5 marks
- 6(b)(i) Tertiary protein structure5 marks
- 6(b)(ii) End-group content of polystyrene5 marks
- 6(c)(i) Cyclization of a beta-hydroxy phenethylamide5 marks
- 6(c)(ii) Terylene from p-xylene5 marks
- 6(d) Fischer indole synthesis5 marks
- 6(e) Acid equivalent of nylon-6,65 marks