General Chemistry 203 101C0
Test 1 (Open Book : Chemical Priciples, Atkin & Jones 5th Edition)
October 21, 2005
1. Consider the following statements about the electromagnetic radiation and
decide whether they are ture or false. Explain your answer or make a
correct example about the false ones. (15)
(a) As the temperature of a black body increase, the wavelength at which
the maximum intensity is found increase.
(b) photons of IR radiation are higher in energy than photons of UV
radiation
(c) Heisenberg uncertainty principle can not be applied to the
electromagnetic radiation at 0k
(d) the kinetic energy of an electron ejected from a metal surface when
the metal is irradiated with UV is independent of the frequency of
the radiation
(e) the electrons that hit a metal surface and can result in the
diffraction pattern have to have the speed of light
2. With the given electron density contour below:
.....figure.....
(a) draw the infromation from each figure by first determining the
corresponding n and l values. Explain. (6)
(b) draw the radial probability distribution along the directions that have
the maximum probability for each plot. (6)
3. Using the model of "particle in the box" and the data in Table 2.4 to
estimate the energy difference for the ground-state π-electrons in
ethylene (CH2CH2) and in butadiene (CH2CHCHCH2). (10)
4. Write the lewis structure, including typical contributions to the
resonance structure (where appropriate, allow for the possibility of
octet expansion). (10)
(a) dihydrogen phosphate (d) phosphorous acid
(b) chlorite ion (e) chlorine nitrate
(c) chlorate ion
5. infrared spectroscopy is an important tool for studying vibrations of
molecules. Just as an atom can absorb a photon of suitable energy to move
an electron from one electronic state to another. a molecules can absorb
a photon of infrated radiation to move one vibrational energy level to
another. In the IR spectroscopy, it is common to express the energy in
cm^(-1) (wave-number).
(a) the N-H vibration (as in p.85) is about 3400 cm^(-1). How much energy
in joule for the N-H vibration would be absorbed by 1.00 mol of the
molecules. (6)
(b) The electronic transitions are usually in the UV-visible region.
Estimate the energy in joules that will be required for a transition
as in figure 1 of p.124. (6)
6. Draw the 3-D structure for the following molecules and describe the
hybridization of the central atom. (10)
(a) NH3 (b) HN3 (c) H2SO4 (d) HNO3 (e) SF4
7. Draw the VSEPR structure (including the long pairs) and predict the bond
angles involving the central atom for the following compounds. (10)
(a) COCl2 (b) CH3 (c) XeOF2 (d) IF3 (e) BrO3
8. Consider a hypothetical species of HeH:
(a) What charge should be present on the species to allow the most stable
molecules. Explain by drawing the MO energy diagram. (5)
(b) If the charge on this species where increased or decreased by one, what
whould be the effect on the bond order for the molecule. (5)
9. Consider the molecules H2CCH2, H2CCCH2, and H2CCCCH2:
(a) Draw Lewis structures for these molecules. (3)
(b) What is the hybirdization at each carbon atom. (5)
(c) describe the C-C bonds and predict the C-C-C angles in these
molecules. (5)
(d) Do all the hydrogen atoms lie in the same plane in each molecules.
Explain. (3)
10. Draw the MO evergy diagrams and predict the bond order and the
magnetism for the following species. (15)
(a) [O2]- (b) [O2}+ (c) [O2]2- (d) N2 (e) B2
共120分,祝各位電機強者都有破百的成績~
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 59.104.2.192