The difference between these two latter substances was first pointed out by Cronstedt, and in 1778 C. Scheele prepared molybdic acid from the sulphide.
Sulphuretted hydrogen, H 2 S, a compound first examined by C. Scheele, may be obtained by heating sulphur in a current of hydrogen, combination taking place between 200° C. and 358° C., and being complete at the latter temperature, dissociation taking place above this temperature (M.
Scheele and named Olsiiss (principe doux des huiles - sweet principle of oils), and more fully investigated subsequently by M.
Scheele had done, and because he was employing a glass vessel he got "fluor acid air" (silicon fluoride).
Oh) 3, a tetrahydroxytribasic acid, first obtained in the solid state by Karl Wilhelm Scheele, in 1784, from the juice of lemons.