Carbohydrate group defined

Gay–Lussac and Thenard was that carried out in 1810 on the combustion analysis of vegetable and animal substances. Lavoisier’s published organic analysis had made use of oxygen gas; but the two young chemists greatly extended the generality of this method by using an oxidizing agent, potassium chlorate. On the basis of their analysis they divided vegetable compounds into three classes according to the proportion of hydrogen and oxygen they contained. The class (containing starch and sugar) in which hydrogen and oxygen were in the same proportions as in water corresponds to the carbohydrates. Although in this joint research it is impossible to separate the contributions of Thenard from those of Gay–Lussac, one has the impression that Thenard usually came second to his friend in the quality, originality, and precision of his research.

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