Formalin Market Overview: Formaldehyde is an organic molecule with the formula CH2O(HCHO) that occurs naturally. Because the pure chemical is a pungent-smelling colorless gas that spontaneously polymerizes into paraformaldehyde, it is kept as an aqueous solution (formalin). RCHO is the most basic of the aldehydes. This substance's common name derives from its resemblance to and relationship to...