Chemistry Industrial Chemistry PMDC Conceptual Practice
PMDC Verified Question 29 of 41
Rayon is classified as a semi-synthetic regenerated fiber manufactured from which natural polymer feedstock?
A
Petrochemical acetyl chloride
B
Synthetic ethylene oligomers
C
Petroleum-derived acetylene
D
Natural cellulose
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: Natural cellulose
Concept:

Rayon is a regenerated semi-synthetic fiber produced by chemical solubilization and re-precipitation of naturally occurring cellulose derived from wood pulp or cotton linters.

Formula / Reaction:

$$[\text{C}_6\text{H}_7\text{O}_2(\text{OH})_3]_n \xrightarrow{\text{NaOH, }\text{CS}_2} \text{Cellulose Xanthate} \xrightarrow{\text{H}_2\text{SO}_4} [\text{C}_6\text{H}_7\text{O}_2(\text{OH})_3]_n \quad (\text{Rayon Fiber})$$

Solution:

  • In the Viscose process, natural cellulose is treated with alkali and carbon disulfide to form a soluble xanthate, which is extruded through spinnerets into an acid bath to regenerate cellulose fibers.


Why other options are incorrect:

  • Acetyl chloride: An organic acylating reagent, not a polymer precursor for rayon.


  • Ethylene and Acetylene: Petrochemical hydrocarbons used in purely synthetic polymers (e.g., polyethylene, polyacetylene).

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