Calculate the number average and weight average molar mass, as well as the dispersity, for a sample of polystyrene made by blending five separate fractions, each of which has a very narrow molar mass...

Calculate the number average and weight average molar mass, as well as the dispersity, for a sample of polystyrene made by blending five separate fractions, each of which has a very narrow molar mass distribution, as follows. Sketch the lamellar structure of a semicrystalline polymer, including details of how polymer molecules are arranged in such a structure. Explain your sketch briefly in a couple of sentences. For each of the following statements, indicate whether it is True or False, and explain briefly your answer. An addition polymerization is also a chain growth polymerization. An isotactic polymer can be synthesized by free radical polymerization. The mechanical properties of polymers can be improved by alignment of molecules caused by stretching or shearing during processing. The higher molar mass fractions of a polymer go through a GPC column more slowly, enable us to measure the average molar mass and molar mass distribution in a polymer. A polymer molecule coils up more in a good solvent than in a bad solvent.