課程名稱︰無機化學一
課程性質︰必修
課程教師︰林英智
開課學院：理學院
開課系所︰化學系
考試日期（年月日）︰105/1/12
考試時限（分鐘）：130分鐘
1.(a) Draw and determine the point group of the folling moleceles:
(Ⅰ) Benzene C6H6
(Ⅱ&Ⅲ) (η^5-C5H5)2Fe(ring-eclipsed and staggered)
(Ⅳ) CH2=C=CH2 (show stereo structure).
(b) The total number of symmertry operations os allene (iv,above) is 8.
Write down all symmetry operations and draw rotaional axis for all of
them invoving rotation. Howmany classes (representations)are there?(10%)
2.(a) Use molecular orbital theory to explain why oxygen (O2) and B2 molecules
are paramagnetic and C2molecule is diamagnetic.
(b) Find the spectroscopic terms (term symbol) of C atom and the number of
total microstate for each of them.
Among those terms, give the ground state.
(c) Use the molecular term symbol to describe the ground state of the
followed molecules: C2,O2,B2.(15%)
3.(a) Calculate the radius ratio of the face-centered packing atom and atoms
that fill in the tetrahedral hole.
(b) In a face-centered cubic structure if half of the tetrahedral holes
are filled by a smaller atom, what is the total packing efficiency?
(c) Give the ratio of packing atoms:tetrahedral:octahedral hole.
(d) Use ABC notation (PA,OA,TA etc.) to describe theposition of packing atom,
tetrahedral hole and octahedral hole for both ccp and hcp closet packing
in proper order.(15%)
4.Use the following parameters
E(BF3) =9.88 E(BF3) =1.62
E(BMe3) =6.14 E(BMe3) =1.70
E(pyridine)=1.17 E(pyridine)=6.40 (in the unit of [kcal/mol]^1/2)
to calculate ΔH (in the unit of kJ/mol) for the reactions of
(Ⅰ) pyridine and BF3 and (Ⅱ) pyridine and BMe3.
Compare your results with the experimental values of -71.1 kJ/mol for
pyridine-BMe3 and -105 kJ/mol for pyridine-BF3. Explain the differences
in terms of HSAB and interms of the structure of BF3 and BMe3.(10%)
5.(a) CsI is much less soluble in water than CsF,and LiF is much less soluble
than LiI. Why?
(b) How does the Ligand Close Packing approach and π-interacion (two
somewhat similar methods) account for the Lewis acidity order of
BBr3>BCl3>BF3.(10%)
6.(a) Three pKa valus of H3Po4 are 2.15, 7.20 and 12.30. Draw a distribution
diagram which is agraph showing the fractio changes of H3PO4(-),HPO4(2-),
PO4(3-) verse pH value. Label the scale and crucial points carefully.
(b) The reaction of Lewis acid-base form adduct. Draw the structure of the
product of B(C6F5)3 and phosphine PH(C6Me3H2)2 which form a frustrated
Lewis pair.(10%) / \
—— 　 ——
// \\ // \\
＿// \\＿P＿// \\＿
\ / \ /
\ / \ /
＝＝ ＝＝
\ /
7. Use the Born-Haber cycle to calculate the enthaloy of formation for KBr
Crystallized in NaCl Lattice. You need to calculate the lattice energy
by the Born-Mayer Eq. using the
Madelung constant 1.748 and interionic distance K-Br of 320pm;
ΔHvap(Br2) = 29.8 kJ/mol;
BDE(Br2) = 190 kJ/mol;
ΔHsup(K) = 79 kJ/mol;
Ionization energy(K) = 418.8 kJ/mol;
electron affinity(Br)= 324.7 kJ/mol;
[e^2/4Πε0]=2.307*10^-28 Jm. Use proper sign for Calculation. (10%)
8.(a) Draw the bandstructures firn-type and p-type semi conductor, mark the
Fermi Level .
(b) Draw the band structure for a p,n-junction and briefly explain how
LED and photovotaic cell work across the p,n-junction.(10%)
9.The absorption peak of I2 vapor shift from 520nm to 450nm when dissolved
in MeOH. Use the halogen bond andMO theory to explain.(10%)