精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰無機化學一 課程性質︰系定必修 課程教師︰王瑜 開課學院:理學院 開課系所︰化學系 考試日期(年月日)︰2009/1/12 考試時限(分鐘):三四節 試題 : 1. give the seven crystal systems and the minimum symmetry required for each system. 2. Au and Ag metal are frequently used for surface studies. They both belong to face centered cubic (F.C.C) ; Describe the surface of (100) (110) (111) 3. diamond is F.C.C with a=3.57埃 and C at (0,0,0) and (1/4, 1/4, 1/4) a. how many C atoms in the unit cell, where are they? b. What is the density of the diamond ? c. What is the C-C distance and the coordination number of each C? (atomic weight of C=12g/mol) 4. graphite is primitive hexagonal with a=b=2.54埃 , c=6.69埃; And C at (0,0,0)(0,0,1/2)(1/3,2/3,0)(2/3.1/3,1/2) a. describe the structure of graphite b. compare the density with the diamond c. compare the C-C distance and the coordination number of each C d. compare the hybridization orbitals of C in diamond and graphite. 5. benzene is planar with D6h symmetry. a. briefly describe the bonding around the each carbon b. illustrate the delocalized πbonding of the system c. explain why it is aromatic, so as the naphthalene(C10H8) and phenanthlene (C14H10) d. Extend the bonding scheme to graphite and explain why diamond is an insulator but graphite is a moderate conductor. 6. there are three atom types in a primitive cubic with a=4埃: Atom A is located at (0,0,0) . atom B is located at (1/2,1/2,1/2) and atom X are located at (1/2,0,1/2) (1/2,1/2,0) (0, 1/2, 1/2) . what Is the formula of the solid? What is the coordination geometry of each atom(include coordination number and interatomic distances) 7. complete the Born –Harber cycle to obtain the enthalpy of formation , Δ Hf of MgO(s). Bond energy of O2=247KJ/mol ,ΔH(sub)(Mg)=37KJ/mol , 2nd ionization E of Mg =1451 KJ/mol, 2nd affinity=-744 KJ/mol, lattice enthalpy =-3932KJ/mol. a. does the ΔHf indicate the favorable on the formation of MgO solid? b. Which energy is the dominant factor in the cycle? c. How does itsΔHf compare with that of LiF and AgCl withΔHf=-796 and 73 KJ/mol respectively. 8. briefly describe the basic concepts of diode , photovoltaic and light emmiting diode(LED) 9. H3 can be either in linear or in triangle geometry. Construct the molecular orbitals for both cases. Assuming the H-H bond enthalpy is the same, predict which geometry is more stable for H3+ and H3- respectively. Explain. -- -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 123.204.156.24