Polyethylene can crystalline in crystallites with the chains aligned in an orthorhombic unit cell with dimensions of 740 pm x 493 pm x 253 pm. Each unit cell contains two complete repeating units of CH:CH2. Calculate the crystallographic theoretical density of fully crystalline polyethylene. Look up a literature value for the density of high density polyethylene (HDPE) and compare to your answer.

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Q: Draw a triclinic unit cell and mark on it the (100), (010), (001), (011), (101), and (110) planes.

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Q: is thought that a solid substance has an orthorhombic structure. Since the edges of the unit cell…

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Q: Draw an orthorhombic unit cell and mark on it the (100), (010), (001), (011), (101), and (110)…

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Q: how do you calculate the planar density (100) and (110) of a simple cubic structure

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Q: Question attached

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Polymers

Polymers are naturally occurring or synthetically produced large molecules or compounds which are made up of series of repeating units called monomers. They are joined together by chemical bonds. The term polymer is coined from Greek roots meaning 'many parts' and are found almost everywhere from the plastics bags to the rubber of our tires to our DNA strands.