HNO3 is the molecular formula for which acid ?
Perrhenic acid Perrhenic acid Perrhenic acid is the chemical compound with the formula . It is obtained by evaporating aqueous solutions of . Conventionally, perrhenic acid is considered to have the formula , and a species of this formula forms when rhenium(VII) oxide sublimes in the presence of water or steam. When a solution of is kept for a period of months, it breaks down and crystals of are formed, which contain tetrahedral For most purposes, perrhenic acid and rhenium(VII) oxide are used interchangeably. Rhenium can be dissolved in nitric or concentrated sulfuric acid to produce perrhenic acid. The structure of solid
Tannic acid sulfuric acid in red flocks. (Stenhouse, Ann. Ch. Pharm. xlv. 16.) <br>According to Rochleder (ibid lxiii. 202), the tannic acid of black tea is the same as that of oak-bark. In 1880, Etti gave for it the molecular formula CHO. He described it as an unstable substance, having a tendency to give off water to form anhydrides (called phlobaphenes), one of which is called "oak-red" (CHO). For him, it was not a glycoside. In Allen’s "Commercial Organic Analysis", published in 1912, the formula given was CHO. Other authors gave other molecular formulas like CHO, while another formula found is CHO.