Q8.2.a: What is the energy of the sixth electronic energy level (N=6)
of a hydrogen atom?
1) – 13.6 eV
2) – 2.27 eV
3) + 2.27 eV
4) – 0.38 eV
5) + 0.38 eV
Q.8.2.b
A hydrogen atom is initially in the excited state
(N = 4). It emits a photon and ends up in the
state (N = 2).
Which of the arrows in the diagram represents
this process?
Q.8.2.c
A hydrogen atom is initially in the excited state
(N = 4). It emits a photon and ends up in the
state (N = 2).
What is the energy of the emitted photon?
1) E4 – E2
2) E2 – E4
3) E4
4) E2
5) |E4|
6) |E2|
Q8.2.d Photon emission
Suppose that these are
the quantized electronic
energy levels (K+U) for an
atom. If the atom is
excited to the second
excited state (marked by
a dot), what are the
possible energies of
photons it might emit?
1) 2, 5, and 9 eV
2) 3, 4, and 7 eV
3) 3 or 7 eV
4) 5 or 9 eV
5) 2 eV
Q.8.2.e
A hydrogen atom is initially in the ground state.
It absorbs a photon. This results in ionization of
the atom: H  H+ + e–
If the separated proton and electron have zero
kinetic energy, what was the energy of the
absorbed photon?
1) 13.6 eV
2) –13.6 eV
3) > 13.6 eV
4) < 13.6 eV
5) 0 eV
Q8.2.f Photon absorption
Imagine an atom which only has two electronic
energy levels. The ground state energy is –3.0 eV
and the excited state has an energy of –1.1 eV.
1) The detector will
detect photons of all
energies – none are
missing.
I irradiate a sample containing many atoms with
2) 1.1 eV
visible light which contains photons of all energies 3) 3.0 eV and 1.1 eV
from 1.8 eV up to 3.1 eV.
4) 3.0 eV
5) 1.9 eV
What are the energies of the photons that are
absorbed, and therefore are not detected in the
outgoing light beam?
Q8.2.g Electron excitation of a gas
Suppose that these are the
quantized energy levels (K+U) for
an atom. Initially the atom is in its
ground state (symbolized by a dot).
An electron with kinetic energy
6 eV collides with the atom and
excites it. What is the remaining
kinetic energy of the electron?
1) 9 eV
2) 6 eV
3) 5 eV
4) 3 eV
5) 2 eV
Q8.3.a Photon absorption, cold sample
Light consisting of
photons with a range of
energies from 1 to 7.5 eV
passes through this
collection of objects.
A collection of these
atoms is kept very
cold, so that all are in
the ground state.
What photon energies
will be absorbed from the
incoming light beam, and
therefore will not be
detected in the outgoing
beam (“dark lines”)?
1) 2 eV, 5 eV, 9 eV
2) 3 eV, 4 eV
3) 0.5 eV, 3 eV, 4 eV
4) 4 eV, 7 eV
5) 3 eV, 4 eV, 7 eV
6) None of the above
Q8.3.b Photon absorption, cold sample
Light consisting of
photons with a range of
energies from 1 to 3 eV
passes through this
collection of objects.
A collection of these
atoms is kept very
cold, so that all are in
the ground state.
What photon energies
will be absorbed from the
incoming light beam, and
therefore will not be
detected in the outgoing
beam (“dark lines”)?
1) 2 eV, 5 eV, 9 eV
2) 3 eV, 4 eV
3) 0.5 eV, 3 eV, 4 eV
4) 4 eV, 7 eV
5) 3 eV, 4 eV, 7 eV
6) None of the above