Formaldehyde, HCHO, is the simplest member of the class of organic compounds known as aldehydes. At room temperature formaldehyde is an extremely reactive colorless gas with a suffocating odor. It is commonly sold as an aqueous solution (formalin) or in solid polymeric forms (paraformaldehyde and trioxane). Formaldehyde is used in the manufacture of dyes, in the production of synthetic resins, and in embalming and as a preservative for biological specimens.

Formaldehyde was first intentionally produced by August Hofmann, a German chemist (1818-1892), in 1867. Justus von Liebig had researched aldehydes earlier but had never succeeded in producing formaldehyde. Alexander Mikhailovich Butlerov (1828-1886) had hydrolyzed methylene acetate while trying to form methyl glycol and produced formaldehyde gas. He had noted that the product of the reaction behaved as an aldehydes. Hofmann, in 1867, exposed a mix of methyl alcohol vapors and air over a hot platinum spiral to form stable formaldehyde...