Remarques sur le microdosage du bore et du germanium dans les composes organiques et mineraux

A wet destruction in a Kjeldahl flask followed by spectrophotometric measurement with azomethine H as reagent, combustion in oxygen in a Parr bomb, and destruction by heating with sodium peroxide followed by acidimetric titration of the mannitol—boric acid complex have been tested for the microdetermination of boron in organic and inorganic compounds and compared with the Schöniger-flask method, which fails to give good results in the case of inorganic compounds; the wet-combustion method is the most useful. Similar techniques, combined with the acidimetric titration of the mannitol—germanic acid complex, or spectrophotometric measurement using phenylfluorone as a complexing reagent, or gravimetric determination as GeO₂, have been tested for the microdetermination of germanium, but none of them is entirely satisfactory, for reasons of lack of either universality or precision.