Oxalic acid Oxalic acid Oxalic acid is an organic compound with the formula CHO. It is a colorless crystalline solid that forms a colorless solution in water. Its condensed formula is HOOCCOOH, reflecting its classification as the simplest dicarboxylic acid. Its acid strength is much greater than that of acetic acid. Oxalic acid is a reducing agent and its conjugate base, known as oxalate (), is a chelating agent for metal cations. Typically, oxalic acid occurs as the dihydrate with the formula CHO·2HO. It occurs naturally in many foods, but excessive ingestion of oxalic acid or prolonged skin contact can be dangerous.
2-Hydroxyethyl terephthalic acid Specifically, it is produced in the course of the thermal condensation of terephthalic acid and ethylene glycol: Further dehydration of 2-hydroxyethyl terephthalic acid gives PET. It is also produced by the partial hydrolysis of PET, as catalyzed by the enzyme PETase: 2-Hydroxyethyl terephthalic acid 2-Hydroxyethyl terephthalic acid is an organic compound with the formula HOCHOCCHCOH. It is the monoester of terephthalic acid and ethylene glycol. The compound is a precursor to poly(ethylene terephthalate) (PET), a polymer that is produced on a large scale industrially. 2-Hydroxyethyl terephthalic acid is a colorless solid that is soluble in water and polar organic solvents.