課程名稱︰普通化學甲上
課程性質︰必帶
課程教師︰周必泰
開課學院：理學院/工學院
開課系所︰物理學系/材料科學系
考試日期（年月日）︰2014/01/10
考試時限（分鐘）：160mins (2hrs40mins) 10:20-13:00
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
(Total Score 290)
Questions Relevant to the Midterm Exam (40):
(Questions are taken from old exam, so answer must be exactly right to have
score)
(15) 1. Name the following compounds or apparatus (a) KHCO3, (b). KMnO4,
(c) GaN, (d).滴管, (e)有刻度的量筒 (3 points each)
(15) 2. For the van-der Waals equation of the real gas
Pobs = (nRT/(V-nb))-a(n/V)^2
(a) Define van-der Waals constants a and b (5)
(b) For the following gases, write down the order of van-der Waals constant a
from the
smallest value. (5)
H2, He, CH4, N2, H2O, NH3
(c) At higher pressure such as > 1000 atm pressure calculated from the
van-der Waals equation shows significant deviation from the observed one. Give a reasonable
explanation. (5)
3. a. Joseph Priestley, b. Antoine Lavoisier, c. John Dalton, d. Louis
Gay-Lussac, e. Amedeo Avogadro, f. Robert Boyle, g. J. J. Thomson, h. G. N. Lewis, i. Svante
Arrhenius, j. Jacques Charles
From above name lists, pick the right person who made the contribution to the
following statement.
(a) Who measured e/m =-1.76 x 10^8 C/g. (b) Who named ‘photon’. (c) The
father of modern chemistry, (d) The first chemist/physicist to perform conductivity of
electrolytes in solution. (e) His name is on the highest arward of American Chemical
Society (10).
After Midterm Exam (250)
A. Definition, Explanation and Question (220)
(10) 1. For the A4 family, CO2
molecule forms linear structure (sp), however, structure of SiO2 is observed
as a tetrahedral (sp3). Please explain. (10)
(15) 2. Qualitatively depict the radial distribution of electron density to
explain why 3d orbital is higher in energy than the 4s in the transition
metal. (10) Briefly explain self-consistent field (SCF) method for obtaining
the orbitals of a polyelectronic atom (5).
(10) 3. At 0 K, should the molecule be frozen completely? If not, explain
your answer from the viewpoint of vibrational motion (5). Can you link this
question with Heisenberg’s uncertainty principle? (5)
(15) 4. The vibration is theoretically treated as a harmonic oscillator and
hence a parabolic potential energy curve is expected. In reality, however, it is more
like a Morse type of curve. Please draw the Morse potential and explain the reason. (5)
Accordingly, from this Morse potential curve please locate the zero point energy,
dissociation energy (De) and bond dissociation energy (D0). (10)
(25) 5. (a) Write down the full name as well as explain the VSEPR model (5).
(b) Draw the Lewis structures and geometry for the following molecules: a. XeF2, b.
SO2, c. I3-, d.BeCl2, e. KrF4 (10). (c) What type of hybridization orbital for Xe in XeF2,
center I in I3-and Kr in KrF4 (5). (d) How many vibrational modes for I3-? (5)
(10) 6. OCN- and CNO- are isomers. Write down the most stable Lewis structure
for OCN- and CNO- (5). Determine and explain which one (OCN- or CNO-) is a
more stable form (5).
(15) 7. (a) Please draw the relative energy level for electronic, vibrational
and rotational and nuclear magnetic resonance (NMR) transitions.(5) (b) Their
energies are respectively in which range, for example X-ray, Infrared,
UV-Visible, radio frequency or microwave? (10).
(15) 8. For a radiation of wavelength at 500 nm, calculate the energy per
photon in terms of cm-1. (5) Also, calculate the energy per mole of the
photons in terms of kcal/mol (5). Calculate the energy of an electron under
1V voltage in terms of (a) cm-1 and (b) kcal/mol (5) Hint: charge of
electron: 1.6 x 10^-19 coulomb, h: 6.62 x 10^-34 Js, c: 3 x 10^8 m/s
(15) 9. In one dimensional vibrational motion for a diatomic molecule AB
(with mass ma for A atom and mb for B atom) along the x axis where the potential energy
is assumed to be ½ kx^2 (k = force constant), write down the Hamiltonian for the Schrö
dinger equation. (10) In general we realize that C=C bonding energy (~615 kJ/mol) is
greater than that of the C-H bond (~410 kJ/mol). However, the C=C stretching
vibrational frequency of ~1600 cm-1 is much smaller than that of C-H stretching (~3000
cm-1). Please explain (5).
(20) 10. Based on the MO theory, what is the bond order for O2, O2- and O2+? And
which one has the highest ionization energy? (10) (5) Does O2 have IR absorption
spectrum? Explain (5). Does O2 have microwave absorption spectrum? Explain (5).
(15) 11. (a) According to the wavefunction written below, please assign which
orbital it belongs to? (10) (b) Write down the corresponding magnetic quantum number for
each 6 wavefunction, i.e., orbital (5).
(20) 12. For linear molecule, the rotational energy is given by
EJ=(h^2/(8pi^2*I))*J(J+1)
I=mu*Re^2
mu: reduced mass
Re:average (equilibrium) bond length
(a) What will be the frequency (v) of the rotational transition from Ji to Ji
+ 1 (5)
(b) You should find from (a) that the frequency (v) will increase as Ji
increases.
However, in reality, the frequency (v) starts to decrease at very high
rotational quantum number of Ji. Explain. (5)
(c) The bond length of 1H35Cl is 126 pm. Calculate the required
electromagnetic radiation (in terms of cm-1) for the rotational transition
from J = 2 to J = 3. (10)
(35) 13. The NMR peaks of compound named “NTU” is shown below. Also
attached is
the intensity ratio. Please answer the following questions.
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1. (a)In the above spectrum the reference TMS is not shown. Draw the
structure of TMS (5).
(b)Where should be the TMS NMR peak (in which ppm)? (5)
(c) Give the definition of ppm (5).
(d) What does it mean when we say down field shift of the NMR peak? (5)
2. Which of the following compounds matches the above NMR spectrum? (10)
And assign a, b, c, d and e peaks in the spectrum to the respective hydrogen of
the“NTU”molecule. (5)
B. Multiple choices (single answer, five points each) (30)
1. Which molecule has the smallest bond angle?
(a) O3 , (b) OF2 , (c) HCN, (d) SSe2, (e) cannot determine
2. Which is the electron configuration of the element with atomic number 72
(Hf)?
(a) [Xe]6s^24f^(14)5d^2, (b) [Xe]6s^24f^(14)5d^16p^1, (c) [Xe]7s^24f^(14)5d^2,
(d) [Kr]7s^24f^(14)6d^2, (e) [Xe]7s^24f^(14)7p^2
3. Which of the following is paramagnetic?
(a) B2, (b) C2, (c) H2, (d) N2, (e) At least two of the above are paramagnetic.
4. What is the probability of finding a particle in a one-dimensional box in
energy level n=4 between x=L/4 and x=L/2? (L is the length of the box)
(a) 12.5%, (b) 25%, (c) 33%, (d) 37.5%, (e) 50%
5. For a particle in a cubic box, how many degenerate energy levels have
energy equal to 14h^2/8mL^2, in which L is the length of the cubic box.
(a) 1, (b) 3, (c) 6, (d) 8, (e) 12
6. Order the following species with respect to the carbon-oxygen bond length
for CO, CO2, CO3^(2-), CH3OH