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1. Give five characteristics for the following types of materials: a. Metals b. Ceramics and glasses c. Polymers 2. Define the isomers and give one example for that? 3. What are the main types of polymers molecular structure? 4. What are the effects of the crystallinity on the mechanical properties of polymers? 5. Give five characteristics of thermoplastic and thermosetting polymers? 6. What are the characteristics of elastomers polymer and what is the reason for this polymer to returns to its original shape on unloading? 7. Name five types of polymer additives and for each indicate how it modifies the properties? 8. Define the glass transition temperature and sketch its relation with the melting temperature? 9. What are the thermal properties of polymer bellow and above the glass transition temperature? 10- What are the classifications of ceramic materials? 11- What are the characteristics of glass-ceramics? 12- What are the characteristics of diamond and graphite? 13- What is the meaning of fracture toughness? 14- What is the reason for the low value of thermal conductivity of ceramics compared to metals