… AND SULPHONAMIDES GENERAL The organo-inorganic compounds covered by headings 29.30 and 29.31 are organic compounds … (or compound derivatives). Headings 29.32 to 29.34 cover heterocyclic compounds. The term " heterocyclic " …
… 2811.22 ‑ ‑ Silicon dioxide 2811.29 ‑ ‑ Other This heading covers mineral acids and anhydrides and other oxides of … ( heading 38.24 ). (N) COMPLEX ACIDS This heading also covers chemically defined complex acids consisting of two or …
