Question

for the perovskite structure (shown below) 14. Coordination numbers of Ti". Ba?' and are, respectively: a. 6, 6, and 6 b. 12,6, and 6 c. 6, 16, and 8 d. 6, 12, and 6 15. In the cesium chloride (CCI) structure, cations are located at a cach of the corners of cubes b. the centre of cubes c. interior tetrahedral sites d. interior octahedral sites 16. Low density polyethylene (LDPE) is a. a linear polymer b. a branched polymer c. a crosslinked polymer d. a network polymer 17. Thermoplastic polymers a. soften when heated and harden when cooled b. include crosslinked and network polymers c. do not soften upon heating d. a and b 18. Spherulites a. are represented by the chain-folded model b. consist of crystalline and non-crystalline rejoins c. are polymer analogue of grains in polycrystalline metals and ceramics d. bande 19. Degree of polymerization represents a. the relationship between number-average and weight-average molecular weights b. the percent of a polymer crystallinity c. the average number of repeat units in polymer chains d. the fraction of a monomer that has polymerized 20. Large elastic extension of rubber materials depends on a. the average molecular weight of polymers b. intertwining and entanglement of neighboring polymer chains c. their degree of polymerization d. the ratio of M, to Mw Page 3 of 7

Answer 1

14. Coordination numbers of Ti 9+ Bet and o2+ for the perovskile structure are, ropeetively! @ 6,12, and 6 15. In the cesium chloride (Csui) structure, cations are located at. o the centre of webes. 16. Low density polyethylene (2DPE) IS © a branched polymer, 17. Thermoplastic polymers- @soften when heated and harden when leoleo, 18. Spheruliles - @ are represented by the chain - folded model 19. Degree of polymerization represents c) the average number of repeat units in polymex chain. 20 large elastic extension of rubber materials depends on intertwining and enteroglement of neighboring polymey chain's.