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Polyvinyl chloride, also called Polychloroethene or PVC, is a thermoplastic. It turns soft when heated and hard when cooled. Polyvinyl chloride is made by polymerization of the monomer vinyl chloride ( chloroethene) CH 2 =CHCl. PVC can be made softer and more flexible by adding plasticizers. Phthalates are often used to soften PVC in this way.
Covariant formulation. v. t. e. Electricity is the presence and flow of electric current. Using electricity, we can transfer energy in ways that allow us to do simple chores. [1] Its best-known form is the flow of electrons through conductors such as copper wires . The word "electricity" is sometimes used to mean "electrical energy ".
