Formula: FeCl₃•6H₂O Formula Weight: 270.30 Description: 0.025% (w/v) Aqueous Solution

Formaldehyde is a naturally occurring organic compound with the formula CH2O and structure H-CHO. The pure compound is a pungent, colorless gas that polymerises spontaneously into paraformaldehyde, hence it is stored as an aqueous solution, which is also used to store animal specimens.