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Chapter 10

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Chapter 10
Chapter 32
The Atom and the Quantum
When Rutherford directed a beam of
alpha particles into gold foil, most of the
alpha particles
a.
b.
c.
d.
were stopped.
bounced back.
continued straight through.
underwent small deflections.
When Rutherford directed a beam of
alpha particles into gold foil, most of the
alpha particles
a.
b.
c.
d.
were stopped.
bounced back.
continued straight through.
underwent small deflections.
Explanations: Some particles were deflected, but most
went through as if the foil were empty space. Only a
few bounced back.
Which of these is largest in size?
a.
b.
c.
d.
An electron
An alpha particle
The nucleus of a gold atom
All about the same.
Which of these is largest in size?
a.
b.
c.
d.
An electron
An alpha particle
The nucleus of a gold atom
All about the same.
Explanation: An electron can reside in any nucleus as
a beta particle ready to be released, and an alpha
particle is the nucleus of a helium atom, much
smaller than a gold nucleus.
An electron in a cathode ray is
a. distinct from an electron that makes up
lightning.
b. related but different from electrons whose
acceleration produces light.
c. like any other electron.
d. None of the above.
An electron in a cathode ray is
a. distinct from an electron that makes up
lightning.
b. related but different from electrons whose
acceleration produces light.
c. like any other electron.
d. None of the above.
Comment: A premise of physics is that all electrons are
identical.
Electron beams can undergo
a.
b.
c.
d.
diffraction.
interference.
deflection.
All of the above.
Electron beams can undergo
a.
b.
c.
d.
diffraction.
interference.
deflection.
All of the above.
The electric charge in a beam of
electrons is
a.
b.
c.
d.
continuous.
quantized.
the same as the charge on a quark.
None of these.
The electric charge in a beam of
electrons is
a.
b.
c.
d.
continuous.
quantized.
the same as the charge on a quark.
None of these.
Comment: Whether or not you know that the charge of a
quark is a fraction of the charge of an electron, what
you should know is that electric charge is quantized.
A beam of electrons has
a.
b.
c.
d.
particle properties.
wave properties.
Both of these.
None of these.
A beam of electrons has
a.
b.
c.
d.
particle properties.
wave properties.
Both of these.
None of these.
A model of an atom is useful when it
a. shows how an atom appears.
b. magnifies what the eye can’t see.
c. helps to visualize processes that are difficult to
visualize.
d. verifies truth.
A model of an atom is useful when it
a. shows how an atom appears.
b. magnifies what the eye can’t see.
c. helps to visualize processes that are difficult to
visualize.
d. verifies truth.
The planetary model of the atom, with
electrons buzzing around the nucleus
like planets orbiting the Sun, is
a. today’s dominant model of the atom.
b. is still helpful in some cases, but has been
replaced by other models.
c. complete nonsense.
d. useful in primitive societies only.
The planetary model of the atom, with
electrons buzzing around the nucleus
like planets orbiting the Sun, is
a. today’s dominant model of the atom.
b. is still helpful in some cases, but has been
replaced by other models.
c. complete nonsense.
d. useful in primitive societies only.
The frequencies of light are nicely
measured using
a.
b.
c.
d.
an electron microscope.
a spectoscope.
interference techniques.
standing-wave analysis.
The frequencies of light are nicely
measured using
a.
b.
c.
d.
an electron microscope.
a spectoscope.
interference techniques.
standing-wave analysis.
The addition of a pair of light
frequencies emitted by an atom often
equals a
a. higher frequency of light emitted by the same
atom.
b. lower frequency of light emitted by the same
atom.
c. composite of all emitted frequencies.
d. None of the above.
The addition of a pair of light
frequencies emitted by an atom often
equals a
a. higher frequency of light emitted by the same
atom.
b. lower frequency of light emitted by the same
atom.
c. composite of all emitted frequencies.
d. None of the above.
Explanation: This follows from two energy transitions in an
atom summing to equal a third energy transition. See
Figure 32.10.
Orbital electrons don’t spiral into the
atomic nucleus because of
a.
b.
c.
d.
angular momentum conservation.
energy conservation.
the wave nature of electrons.
All of the above.
Orbital electrons don’t spiral into the
atomic nucleus because of
a.
b.
c.
d.
angular momentum conservation.
energy conservation.
the wave nature of electrons.
All of the above.
Comment: The wave nature prevents spiraling, not the
conservation principles stated.
The radii of electrons about the atomic
nucleus are nicely understood by
thinking of the electrons as
a.
b.
c.
d.
standing waves.
discrete particles.
resonating vibrations.
reflections.
The radii of electrons about the atomic
nucleus are nicely understood by
thinking of the electrons as
a.
b.
c.
d.
standing waves.
discrete particles.
resonating vibrations.
reflections.
The greater the number of protons in
a nucleus, the
a.
b.
c.
d.
larger the outermost electron orbits.
tighter the electron orbits.
looser inner orbits become.
None of these.
The greater the number of protons in
a nucleus, the
a.
b.
c.
d.
larger the outermost electron orbits.
tighter the electron orbits.
looser inner orbits become.
None of these.
A current model of the atom sees
electrons about the atomic nucleus
a.
b.
c.
d.
as if they were tiny planets in orbit.
in shells.
pulled by springlike forces.
as spectral lines.
A current model of the atom sees
electrons about the atomic nucleus
a.
b.
c.
d.
as if they were tiny planets in orbit.
in shells.
pulled by springlike forces.
as spectral lines.
The thing that waves in the
Schrödinger wave equation
a.
b.
c.
d.
is energy itself.
is a wave function,  .
is density amplitudes.
is electron clouds.
The thing that waves in the
Schrödinger wave equation
a.
b.
c.
d.
is energy itself.
is a wave function,  .
is density amplitudes.
is electron clouds.
According to Schrödinger, the location
of an electron in an atom can be
a. at an average distance from the nucleus
described by Bohr.
b. somewhere between the nucleus and the outer
edge of the electron cloud.
c. inside the nucleus.
d. All of these.
According to Schrödinger, the location
of an electron in an atom can be
a. at an average distance from the nucleus
described by Bohr.
b. somewhere between the nucleus and the outer
edge of the electron cloud.
c. inside the nucleus.
d. All of these.
Determining the location of a specific
electron in an atom is
a. not doable without proper tools.
b. probabilistic only.
c. something that Schrödinger and his team of
investigators were the first to do.
d. None of the above.
Determining the location of a specific
electron in an atom is
a. not doable without proper tools.
b. probabilistic only.
c. something that Schrödinger and his team of
investigators were the first to do.
d. None of the above.
Subatomic interactions described by
quantum mechanics are governed by
a.
b.
c.
d.
the same laws of classical physics.
laws of certainty.
laws of probability.
exact measurements.
Subatomic interactions described by
quantum mechanics are governed by
a.
b.
c.
d.
the same laws of classical physics.
laws of certainty.
laws of probability.
exact measurements.
According to the correspondence
principle,
a. new theory must agree with old theory where
they overlap.
b. the Schrödinger atom is a special case of the
Bohr model of the atom.
c. de Broglie’s matter waves are much the same
in nature as sound waves.
d. All of the above.
According to the correspondence
principle,
a. new theory must agree with old theory where
they overlap.
b. the Schrödinger atom is a special case of the
Bohr model of the atom.
c. de Broglie’s matter waves are much the same
in nature as sound waves.
d. All of the above.
Comment: The statements about the Schrödinger atom
and de Broglie’s matter waves are false!
The correspondence principle
applies to
a.
b.
c.
d.
submicroscopic phenomena.
macroscopic phenomena.
gravitation and quantum theories.
all good theories.
The correspondence principle
applies to
a.
b.
c.
d.
submicroscopic phenomena.
macroscopic phenomena.
gravitation and quantum theories.
all good theories.
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