Explanatory notes
… Ferric oxide (Fe 2 O 3 ). Obtained from dehydrated ferrous sulphate or natural iron oxide. Finely divided powder, … is classified in this heading), or mixed with clay, calcium sulphate (Venetian red), etc. (it then falls in Chapter 32 … state as an antidote to arsenic poisoning. It is an amphoteric hydroxide which, after oxygenation, gives the …