Two pet compounds

  The two "pet" compounds that I pick for further research are stainless steel and PVC.

  Stainless steel got its name becausee it is not easy to leave any stains on it.It was first discovered by Harry Brearley in 1912, when he was seeking for an alloy that was sorrosion resistant for gun barrels. The key element in the stainless steel is the chromium. When there is more than 12% of the chromium in the steel, the chemical reaction will form a passivation layer covering the metal that protects it from air, water or any other acid and alkali. There are other elements that changes the hardness and ductibility of the steel, so that it could meet the demands for different applications. It can be used in various ways, such as building construction, trasportations, knives and cookers.

  When I was doing the research, I found a vedio clip that uses stainless steel drum to play. It's very cool!

  PVC is short for Polyvinyl Chloride. It was accidentally discovered twice in 1835 by Henri Victor Regnault and in 1972 by Eugen Baumann. The two substances discovered were exposed under sunlight and turned into white solids. Its Resin identification code is 3. It has a large usage amount in the world. Its physical property is stable, heat resisting, not easily corroded by acid and alkali. It can be used for the product of clothes, upholstery, tubes etc. There are some toxic additives in PVC, so it can't be used for food containers. When burning the PVC, it will produce dioxin that is polluting to the air.