These materials represent a significant fraction of petroleum. They are refined by vacuum distillation. Paraffin waxes are mixtures of saturated n- and isoalkanes, naphthenes, and alkyl- and naphthenesubstituted aromatic compounds. The degree of branching has an important influence on the properties. Millions of tons of paraffin waxes are produced annually. They are used in foods (such as chewing gum and cheese wrapping), in candles and cosmetics, as non-stick and waterproofing coatings and in polishes. Paraffin wax refers to a white or colorless soft solid that is used as a lubricant and for other applications. It is derived from petroleum and consists of a mixture of hydrocarbon molecules containing between twenty and forty carbon atoms. It is solid at room temperature and begins to melt above approximately 37 °C (99 °F); its boiling point is >370 deg C. In chemistry, paraffin is used synonymously with "alkane", indicating hydrocarbons with the general formula CnH2n+2. The name is derived from Latin parum ("barely") + affinis, meaning "lacking affinity" or "lacking reactivity" indicating paraffin's unreactive nature. The hydrocarbon C31H64 is a typical component of paraffin wax Paraffin wax is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 46 and 68 °C (115 and 154 °F), and having a density of around 900 kg/m3 . It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents but burns readily. Paraffin wax is an excellent electrical insulator, with an electrical resistivity of between 1013 and 1017 ohm metre. This is better than nearly all other materials except some plastics (notably Teflon). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron. Paraffin wax is an excellent material to store heat, having a specific heat capacity of 2.14– 2.9 J g−1 K −1 (joule per gram kelvin) and a heat of fusion of 200–220 J g−1 . This property is exploited in modified drywall for home building material: a certain type (with the right melting point) of wax is infused in the drywall during manufacture so that, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat. Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover. Wax expands considerably when it melts and this allows its use in wax thermostatic element thermostats for industrial, domestic and, particularly, automobile purposes

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