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CBSE Class 12 · 2005 · Delhi · Aldehydes Ketones and Carboxylic AcidsVery Short Answer

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How are formalin and trioxane related to methanal?

Answer: Formalin = 40% aqueous solution of methanal; trioxane = its cyclic trimer (HCHO)₃.

Solution

Formalin is simply methanal dissolved in water (≈40%).
Trioxane is methanal's cyclic trimer, (HCHO) — three CHO units in a six-membered O–CH ring. Both regenerate methanal.

CBSE Class 12 Board · 2005 · Delhi · Subjective

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