… Ammonia, anhydrous or in aqueous solution. …
Explanatory notes
… (2) Other inorganic bases containing no oxygen, such as ammonia (heading 28.14), or hydrazine (heading 28.25), and … (a) The oxides and hydroxides of Chapter 25 , particularly magnesia (magnesium oxide), whether or not pure, and … similar purity, including water treated with ion‑exchange media). (e) Colouring matter with a basis of metal oxides ( …