Test 7: Review B Flashcards
he ratio of the energy of a photon to its frequency is
A) the photon’s wavelength.
B) Planck’s constant.
C) pi.
D) the photon’s speed.
E) not known.
b. Plancks constant
A quantum of light is called a
A) electron.
B) proton.
C) neutron.
D) none of these
d. None of these
Which of the following photons has the greatest energy?
A) red light
B) blue light
C) ultraviolet
D) infrared
c. Blue light
The photoelectric effect best demonstrates the
A) wave nature of light.
B) particle nature of light.
C) both
D) none of these
b. Particle nature of light
Light behaves primarily as a wave when it
A) interacts with matter.
B) travels from one place to another.
b. Travels from one place to another
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
A) blue beam.
B) red beam.
C) both the same
b. Red beam
Quantum uncertainties are most predominant for simultaneously measuring the speed and location of
A) a baseball.
B) an electron.
b. An electron
Two photons have the same wavelength. They also have the same
A) frequency.
B) energy.
C) both
D) neither of these
c. Both
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?
A) the threshold frequency of the ejected electrons
B) the time lag between the absorption of blue light and the start of emission of the electrons
C) the maximum kinetic energy of the ejected electrons
D) the number of electrons ejected per second
E) none of these
D) the number of electrons ejected per second
An electron and a proton are traveling at the same speed. Which has the longer wavelength?
A) the proton
B) the electron
C) Both have the same wavelength.
b. The electron
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
A) radiation rate of the piece of radium.
B) alpha particles that are caught.
C) both
D) neither of these
b. Alpha particles that are caught
Which of the following are conserved when a photon collides with an electron?
A) momentum and energy
B) momentum and velocity
C) energy and velocity
D) momentum, energy, and velocity
a. Momentum and energy
Quantization of electron energy states in an atom is better understood in terms of the electron’s
A) wave nature.
B) particle nature.
C) neither of these
a. Wave nature
A beam of electrons has
A) wave properties.
B) particle properties.
C) both
D) neither of these
c. Both
Heavy atoms are not appreciably larger in size than light atoms because the nuclei of heavy atoms have more
A) nucleons.
B) electric charge.
C) mass.
D) all of these
E) none of these
b. Electric charge
Most alpha particles fired at a gold foil pass through undeflected because the
A) net charge of the gold atoms is zero.
B) gold atoms, unlike most other metal atoms, are relatively far apart.
C) electric field is zero inside the gold.
D) atoms of gold, like any others, are mostly empty space.
E) none of these
D) atoms of gold, like any others, are mostly empty space.
A new theory conforms to the correspondence principle when it
A) accounts for verified results of the old theory.
B) updates the essence of the old theory.
C) ties two or more theories together.
D) corresponds to all theories in nature.
E) none of these
A) accounts for verified results of the old theory.
Orbital electrons do not spiral into the nucleus because of
A) the large nuclear size compared to the electron’s size.
B) angular momentum conservation.
C) the wave nature of the electron.
D) electromagnetic forces.
E) none of these
C) the wave nature of the electron.
The electrical force between an inner electron and the nucleus of an atom is larger for atoms of
A) high atomic number.
B) low atomic number.
C) the same for both
a. High atomic number
The quantum-mechanical probability cloud for the electron in the hydrogen atom has an average radius
A) quite different from the radius predicted by Bohr.
B) that agrees with the orbital radius of Bohr.
b. That agrees with the orbital radius of Bohr