65. Changeable shape2. We know that an element is organic because it is formed by carbon.
66.
67. Low-density polyethylene is more flexible than high-density polyethyleneTHERE ARE MORE THAN THOSE POSSIBILITIES 5. High-density polyethylene is made by petroleum.
68.
69. 10. Polyvinyl chloride is derived from sodium chloride and petroleum. 11. Write some principal uses of the polyvinyl chloride are: Construction, Films, Jars, Blisters, Plugsā¦ 12. Which are the four types of polystyrene? PS crystal, Polystyrene of high place in the environment, Expanded polystyrene and Polystyrene extrudate. 13. Some properties of polystyrene areā¦ (Choose the correct answers). a)It can float in the water d) It hasnāt got resistance to high temperatures