Xylathoric acid is a corrosive agent used for many functions, including thermalizing the landing deck on Pernaia Prime's moon in the mid-22nd century. In 2152, Jonathan Archer, T'Pol, and Travis Mayweather were told they would have to wait until the process was finished, as it would injure them. It would also not take much xylathoric acid to cause harm, with 0.5 cm of the substance being enough to cause damage to one's feet (or destroy them). (ENT: "The Seventh")