Chem 431 - Winter 1996 - Test 4 - April 4, 1996
Name
SS#
(h=6.626 x 10-34J s ; k= 1.381 x 10-23J K-1 ; c=2.998 x 108 m/s)
(e=1.602 x 10-19C, me=9.1 x 10-31kg, mp=1.673 x 10-27kg)
(10)
1. What is the thermal deBroglie wavelength () and
the
translational contribution to the standard molar entropy
(S) of Ar at 300.0oK?
( 8)
2. What is the vibrational contribution to the standard
molar enthalpy (H)of Cl2 gas at 300.0oK if the
vibrational frequency is 1.678 x 1013s-1?
Chem 431 - Winter 1996 - Test 4 - Page 2
( 4)
3. What is the difference between the e- ejected
ultraviolet
photoelectron
spectroscopy
and
the
ejected in x-ray photoelectron spectroscopy.
in
e-
(10)
4. What are the characteristic rotational temperature and
the rotational contribution to the standard molar Gibbs
Free Energy (G)of Cl2 gas at 300.0oK?
The moment of
inertia of Cl2 is 1.16 x 10-45kg m2.
(10)
5. What would the pressure of 1.00 mole of Cl2 gas at
500.0oK in a container (1.00 x 10-3m3) if the hard sphere
diameter of Cl2 gas is 2.00 x 10-10m?
Chem 431 - Winter 1996 - Test 4 - Page 3
( 3)
6. What are the constraints (things held constant) on the
systems of microcanonical ensemble?
( 8)
7. What is the ratio of constant pressure molar heat
capacity (Cp) and constant volume molar heat capacity
(Cv) at high temperature of HCl according to the
equipartition principle?
( 8)
8. What is the size of a magnet used in tesla in a 200 MHz
1HNMR?(gN=5.585 1.0 T= 1.0 kg C-1s-1)
( 3) 9. Which of the following is the correct equation for the
Lagrange multiplier ?
a.  gi exp(-i/kT)
b. ln(N/q)
c. 1/kT
d. e h/(4mp)
Chem 431 - Winter 1996 - Test 4 - Page 4
( 2) 10. True or False.
It is a fundamental postulate of
statistical mechanics that a system is equally likely to
be in any one of the possible microstates.
( 5) 11. Give the equation and define the
dissociative equilibrium constant?
terms
for
the
( 6) 12. When considering neighboring group contributions to
shielding of two neighboring nuclei which would have a
larger shielding effect if nuclei “A” is twice as far
from the nuclei of interest as the nuclei “B”?
What
would the ratio of the shielding of “A” to “B”? Assume
the magnetic susceptibilities and angles are the same in
both cases.
Chem 431 - Winter 1996 - Test 4 - Page 5
( 2) 13. The difference in shifts () of hydrogens on a molecule
in the 1HNMR is primarily due to atomic shielding
((loc)) or molecule shielding ((neighbor)).
(Circle One)
( 3) 14.
is when two nuclei
have antiparallel spins due to interaction through the
electrons orbiting them.
( 3) 15.
is the condition of strong
effective coupling of two oscillators causing identical
frequencies.
( 3) 16. Electrons ejected from the same electronic level can
have differing velocities depending on their
level.
( 6) 17. How many lines (peaks) would you expect from the
hydrogens on the bolded carbon of CH2CHCHCl? What would
their relative heights be. Draw spectra and label
relative heights.
( 6) 18. What would the local magnetic field felt by a nuclei if
the initial field is 12 tesla and the shielding constant
() is 0.05?