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Christian Schonbein. Portrait of Christian Friedrich Schonbein (1799-1868), German chemist. In 1840 Schonbein investigated the source of the smell that often formed around electrical equip- ment. He discovered that it was an oxygen molecule that contained three atoms rather than the usual two. He named the new molecule 'ozone', the Greek word for 'smell' (ozon). In 1845 Schonbein accidentally discovered that cotton treated with nitric acid formed a smokeless explosive that was 4 times as powerful as gunpowder. This explosive is known as guncotton or nitrocellulose. Despite problems due to its instability, it was later modified by J. Dewar to make cordite.
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