Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 INORGANIC CHEMICALS; ORGANIC OR INORGANIC COMPOUNDS OF PRECIOUS METAL, OFRARE-EARTH METALS, OF RADIOACTIVE ELEMENTS OR OF ISOTOPES 28 11 OTHER INORGANIC ACIDS AND OTHER INORGANIC OXYGEN COMPOUNDS OF NON-METALS. Commodity Code Description 28 11 11 HYDROGEN FLOURIDE (HYDROFLUORIC ACID) 28 11 19 OTHER INORGANIC ACIDS 28 11 21 CARBON DIOXIDE 28 11 22 SILICON DIOXIDE 28 11 29 NITROUS OXIDE