1. Calculate the “characteristic rotational energy,” ℏ2/2I, for
the O2 molecule whose bond length is 0.121 nm.
2. What are the energy and wavelength of photons emitted in an l
= 3 to l = 2 transition?
Answers:
1) 1.79×10−4 eV
2) 1.16 mm
Barium has a work function of 2.48 eV. What is the maximum
kinetic energy of electrons if the metal is illuminated by UV light
of wavelength 420 nm?
eV
What is their speed?
m/s
For a diatomic gas phase molecule, the rotational energy is
given by the expression:
Ej = Be J(J+1)
where J is the rotational quantum number, and Be is
the rotational constant. The degeneracy for rotational states is
given by:
g(J) = 2J+1
The normalization constant (total rotational partition function)
for the Boltmann distribution for rotations is given by:
Q(J,T) = kBT / Be
Iodine, I2(g), has a rotational constant of
Be = 0.037372 cm-1. Determine the fraction of
I2 molecules...
Rotational spectroscopy observe what type of molecule? What is
his energy range? Measured molecule properties.
vibrational spectroscopy observe what type of molecule? What is
his energy range? Measured molecule properties.
Consider an atom with four energy levels, where the lowest
energy is -10 eV and the highest level is 0 eV. Sketch an
energy-level diagram that could produce the spectrum. What are the
energies of the other two energy levels. (Note: there are more than
two answers.)
A -2 eV and -5 eV
B -1 eV and -4 eV
C -1 eV and -6 eV
D -6 eV and -9 eV
E -7 eV and -3 eV
Protons having a kinetic energy of 5.00 MeV (1 eV = 1.60 x 10-19
J) are moving in the positive x direction and enter a magnetic
field B = 0.025 T directed out of the plane of the page and
extending from x = 0 to x = 1.00 m as shown in the Figure below.
(a) Ignoring relativistic effects, find the angle
α between the initial velocity vector of the proton beam and the
velocity vector after the beam...
The equilibrium constant, K, for the following reaction is 2.3 x
10-4 at 300 °C: N2 (g) + C2H2 (g) ⇌ 2 HCN (g). Calculate the
equilibrium concentration of HCN when 0.555 moles of N2 and 0.555
moles of C2H2 are introduced into a 0.500 L vessel at 300 °C.
4. Find the wavelength of radiation whose photons have energy
equal to 1.4 eV.
i. 0.34 ?m
ii. 0.89 ?m
iii. 1.2 ?m
iv. 1.7 ?m
5. Explain (in words, not equations) what the Betz limit is and how
it is derived.