Chapter 7 review B
The half-life of carbon 14 is 5730 years. If a 1-gram sample of old carbon is 1/8 as radioactive as 1-gram of a current sample, then the age of the old sample is about
17,200 years.
Which of the following isotopes is radioactive?
Carbon-14
The ratio of the energy of a photon to its frequency is
Planck's constant
A nucleon is either
a proton or neutron
Fusing two iron nuclei yields a net
absorption of energy
A new theory conforms to the correspondence principle when it
accounts for verified results of the old theory.
Which experiences the greatest electrical force in an electric field?
alpha particle
A radiation detector measures the radioactivity of a piece of radium by catching and counting alpha particles it emits. According to quantum physics, making this measurement affects the
alpha particles that are caught.
Quantum uncertainties are most predominant for simultaneously measuring the speed and location of
an electron
An atom with an imbalance of electrons to protons is
an ion.
Most alpha particles fired at a gold foil pass through undeflected because the
atoms of gold, like any others, are mostly empty space.
When an alpha particle is ejected from a nucleus, the nucleus then has less
both (mass and charge)
Which body is heated in its interior by nuclear processes?
both (the earth and the sun?)
A beam of electrons has
both of these (particle and wave properties)
Energy released by the sun results from the process wherein atomic nuclei
combine
In both fission and fusion, mass
converts to kinetic energy
The origin of cosmic rays is the
cosmos
In the fissioning of uranium, a chain reaction is caused by
ejected neutrons.
Heavy atoms are not appreciably larger in size than light atoms because the nuclei of heavy atoms have more
electric charge
Once an alpha particle is outside the nucleus it is
electrostatically repelled
Two photons have the same wavelength. They also have the same
frequency and energy
Which radiation has no electric charge associated with it?
gamma rays
Plutonium is not found in any appreciable amounts in natural ore deposits because it
has a short half-life
The electrical force between an inner electron and the nucleus of an atom is larger for atoms of
high atomic number.
X-rays may be regarded as
high frequency radio waves
The most abundant element in the universe is
hydrogen
When a lump of uranium is broken into smaller pieces, the total surface area of the lump
increases
A nucleon has the least mass in the nucleus of
iron
Uranium-235, uranium-238 and uranium-239 are different
isotopes
Compared to the mass of a uranium nucleus before splitting, the pieces it splits into have
less mass
Which of the following are conserved when a photon collides with an electron?
momentum and energy
Different isotopes of an element have different numbers of
neutrons.
A quantum of light is called a
none of these
The half-life on an isotope is one day. At the end of three days, how much of the isotope remains?
one-eighth
A nucleon has more mass when it is
outside the nucleus
The photoelectric effect best demonstrates the
particle nature of light.
Electric forces within an atomic nucleus tend to
push it apart
The source of the Earth's natural heat is
radioactive decay in the Earth's core
Two beams of light, a red beam and a blue beam, have the same energy. The beam with the greater number of photons is the
red beam.
Fusing two helium nuclei yields a net
release of energy
Compared to the wavelengths of visible light, the wavelengths of matter waves are relatively
small
When a beta particle is ejected from a nucleus, the nucleus then has slightly
smaller mass and significantly greater charge
The quantum-mechanical probability cloud for the electron in the hydrogen atom has an average radius
that agrees with the orbital radius of Bohr.
An electron and a proton are traveling at the same speed. Which has the longer wavelength?
the electron
Most of the radioactivity we personally encounter comes from
the natural environment
When a clean surface of potassium metal is exposed to blue light, electrons are emitted. If the intensity of the blue light is increased, which of the following will also increase?
the number of electrons ejected per second
Orbital electrons do not spiral into the nucleus because of
the wave nature of the electron.
Light behaves primarily as a wave when it
travels from one place to another
Which of the following photons has the greatest energy?
ultraviolet
Quantization of electron energy states in an atom is better understood in terms of the electron's
wave nature.