课程名称︰普通化学(丙)
课程性质︰森林系/心理系必修
课程教师︰蔡蕴明
开课学院：理学院
开课系所︰化学系
考试日期（年月日）︰2016/05/11
考试时限（分钟）：120分钟
※注: 本次测验附有元素周期表
试题:
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R = 0.08206 liter．atm．K^-1．mol^-1 = 8.3145 J．K^-1．mol^-1 ln(x) = 2.303*log(x)
1. What is the physical meaning of a nodal surface? (5%)
2. What is the physical significance of the value Ψ^2 at a particular
point in an atomic orbital? (5%)
3. The first ionization energies of As and Se are 0.947 and 0.941 MJ/mol, respectively.
Rationalize(解释) these values in terms of electron configuration. (5%)
4. The electron affinity for sulfur is more exothermic than that for oxygen.
How do you account for this? (5%)
5. Use the following standard enthalpies of formation to estimate the N-H bond energy
in ammonia: N(g),472.7 KJ/mol; H(g),216.0 kJ/mol; NH3(g),-46.1 KJ/mol. (5%)
6. (a) Write Lewis structures for OCN¯(C is central atom). Show all resonance structures
where applicable and assign formal charge for each atom. (5%)
(b) Write Lewis structures for CNO¯(N is central atom). Show all resonance structures
where applicable and assign formal charge for each atom. (5%)
(c) Which one of the two compounds is least stable and why?(3 reasons) (6%)
7. Predict the molecule structure for each of the following:
(a) XeCl2 (b) ICl3 (c) TeF4 (d) PCl5 (e) ICl5 (10%)
8. Write the electron configuration and determine the bond order and magnetism of
CO, CO+, and CO2+. (9%)
9. Sketch the orbital pictures showing how two 2P atomic orbitals of two fluorine
atoms overlap to form bonding and antibonding.
Designate the molecular orbitals according to the type of bonding. (4%)
10.Which do you expect to be a stable diatomic molecule, F2(2- or O2(2¯?
Explain. (6%)
11.Would you expect F2 to have a lower or higher first ionization energy than
atomic fluorine? Explain. (5%)
12.What is the formula for the compound that crystallizes with a cubic closest
packed array of sulfur ions, and that contains zinc ions in 1/8 of the
tetrahedral holes and aluminum ions in 1/2 of the octahedral holes?
Explain how you derive the answer. (5%)
13.Consider the following data for Xenon:
Triple point: -121℃, 280 torr
Normal melting point: -112℃
Normal boiling point: -107℃
What is more dense, Xe(s) or Xe(l)? Explain. (5%)
14.The Vapor pressure of water at 25℃ is 23.8 torr, and the heat of vaporization
of water at 25℃ is 43.9 KJ/mol.
Calculate the vapor pressure of water at 50℃. (10%)
15.Draw the MO energy diagram of the πsystem of NO2(N is the central atom).
Indicate how the atomic orbitals are combined for each π-MO. (5%)
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