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Christian Friedrich Schönbein

Christian Friedrich Schönbein (1799 - 1868) was a German-Swiss chemist who is most well-known for his discovery of guncotton. He also discovered ozone, a form of oxygen, in 1840 during the slow oxidation of white phosphorus and the electrolysis of water.

Although his wife had forbidden him to do so, he occasionally experimented at home in the kitchen; one day in 1845, when his wife was away, he spilled a mixture of nitric acid and sulfuric acid. After using his wife's cotton apron to mop it up, he hung the apron over the stove to dry, only to find it spontaneously ignite and burn so quickly that it seemed to disappear. Schönbein had converted the cellulose of the apron into nitrocellulose; the nitro groups (added from the nitric acid) served as an internal source of oxygen, and when heated, the cellulose was completely oxidized, all at once.

Schönbein recognized the possibilities of the compound. Ordinary black gunpowder, which had reigned supreme in the battlefield for the past 500 years, exploded into thick smoke, blackening the gunners, fouling the cannon and small arms, and obscuring the battlefield. Nitrocellulose was a possible "smokeless powder", and from its potential as a propellant for artillery shellss, it received the name guncotton.

Attempts to manufacture guncotton for military use failed at first because the factories had a tendency to blow up; it was not until 1891 that James Dewar and Frederick Augustus Abel managed to compound a safe mixture that included guncotton, called cordite because it could be pressed into long cords.