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Parkesine, the first member of the Celluloid class of compounds and considered the first man-made plastic, is patented by Alexander Parkes. [4] 1869: John Wesley Hyatt discovers a method to simplify the production of celluloid, making industrial production possible. 1872: PVC was accidentally synthesized in 1872 by German chemist Eugen Baumann ...
Celluloids are a class of materials produced by mixing nitrocellulose and camphor, often with added dyes and other agents.Once much more common for its use as photographic film before the advent of safer methods, celluloid's common present-day uses are for manufacturing table tennis balls, musical instruments, combs, office equipment, fountain pen bodies, and guitar picks.
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
The first plastic made from synthetic components, it was developed by Leo Baekeland in Yonkers, New York, in 1907, and patented on December 7, 1909. [ 3 ] Bakelite was one of the first plastic-like materials to be introduced into the modern world and was popular because it could be moulded and then hardened into any shape.
The most commonly produced plastic consumer products include packaging made from LDPE (e.g. bags, containers, food packaging film), containers made from HDPE (e.g. milk bottles, shampoo bottles, ice cream tubs), and PET (e.g. bottles for water and other drinks). Together these products account for around 36% of plastics use in the world.
Neolithic Age (new stone era) beginning about 10,200 years ago: flint tools (diagenesis of marine microfossils, microcristalline opal and chalcedony), jade tools (usually nephrite, jadeitite or jadeite-jade is less common), kaolin earth (adobe bricks made by drying of clay), copper, gold, silver and rocksalt.
He also set about drawing up a list of all the elements – now 33 elements replaced the ancient four. His list was grouped into four categories: gases, non-metals, metals and earths. On top of this, Lavoisier created a classification system for the ever-increasing array of chemicals being discovered.
Lavoisier writes the first modern list of chemical elements – containing 33 elements including light and heat but omitting Na, K (he was unsure of whether soda and potash without carbonic acid, i.e. Na 2 O and K 2 O, are simple substances or compounds like NH 3), [91] Sr, Te; some elements were listed in the table as unextracted "radicals ...