Polymer Materials – Melamine and Formaldehyde Facts (Choose the Incorrect Statement) Which one of the following statements regarding melamine, formaldehyde, and their resin is NOT correct?
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AMelamine is obtained from calcium carbide
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BFormaldehyde is prepared synthetically via routes originating from methane-derived methanol
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CMelamine reacts with formaldehyde to form melamine-formaldehyde resin
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DMelamine-formaldehyde plastics are widely used for electrical insulators and tableware
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EAll statements are correct
Answer
Correct Answer: Melamine is obtained from calcium carbide
Explanation
Introduction:Melamine-based thermosets are staple engineering plastics. The question probes factual understanding of feedstocks and resin formation pathways, asking you to spot the incorrect statement among otherwise correct facts.
Given Data / Assumptions:
- Melamine-formaldehyde (MF) is a thermosetting resin.
- Industrial organic chemistry links methane to methanol and then to formaldehyde.
- Electrical insulation and tableware are common MF applications due to heat resistance and hardness.
Concept / Approach:
Melamine is not produced from calcium carbide. Industrially, melamine is synthesized from urea (which originates from ammonia and carbon dioxide). Formaldehyde is produced by catalytic oxidation/dehydrogenation of methanol, and MF resins are formed by condensation of melamine with formaldehyde under controlled pH/temperature.
Step-by-Step Solution:
1) Check source of melamine: derived from urea, not from CaC2; hence (a) is incorrect.2) Validate (b): formaldehyde is produced industrially from methanol, which is commonly derived from natural gas (methane) via syngas.3) Validate (c): melamine + formaldehyde → MF resin (thermoset network).4) Validate (d): MF plastics show good dielectric strength and heat resistance—used in switches, laminates, crockery.Verification / Alternative check:
Standard polymer chemistry texts and industrial process summaries confirm urea-based melamine production and methanol-to-formaldehyde routes.
Why Other Options Are Wrong:
(b) is acceptable phrasing of the industrial pathway; (c) and (d) are core facts; (e) cannot be true because (a) is false.
Common Pitfalls:
Confusing acetylene chemistry from calcium carbide with melamine production; equating “from methane” to a direct conversion rather than via methanol.
Final Answer:
Melamine is obtained from calcium carbide