(chemistry) An acid known only in its salts (the metatungstates).

(chemistry) An acid obtained by the distillation of terebic acid, and homologous with citraconic acid.

(chemistry) An unstable substance, H₂S₂O₆, known only in its solutions and in certain well-defined salts.

(chemistry) pyroboric acid

(organic chemistry) An organic compound with the chemical formula C₆H₂Cl₂O₄.

(chemistry) A thionic acid, H₂S₃O₆.

propiolic acid

An acid amide derivative of succinic acid.

(organic chemistry) morin

(chemistry) A sulphacid of tin (more exactly called metasulphostannic acid), which is obtained as a dark brown amorphous substance forming a well-known series of salts.