Deck 8: The Nucleus

Question 1

The mass number of the nucleus is

A) 4.
B) 5.
C) 9.
D) 13.

Answer 1

9.

Question 2

Of the following particles, the only one that is not stable outside an atom is the

A) electron.
B) proton.
C) neutron.
D) neutrino.

Answer 2

neutron.

Question 3

A molecule of heavy water contains

A) two oxygen atoms instead of one.
B) three hydrogen atoms instead of two.
C) deuterium atoms instead of hydrogen atoms.
D) a deuterium atom instead of an oxygen atom.

Answer 3

deuterium atoms instead of hydrogen atoms.

Question 4

Which, if any, of the following elements have no radioactive isotopes?

A) hydrogen.
B) potassium.
C) uranium.
D) All of these elements have radioactive isotopes.

Question 5

Which of the following is not an isotope of hydrogen?

A)
B)
C)
D)

Question 6

A particle never emitted in beta decay is the

A) neutron.
B) neutrino.
C) electron.
D) positron.

Question 7

The atomic number of a nucleus decreases when it emits

A) a proton.
B) a neutron.
C) an electron.
D) a positron.

Question 8

Of the following particles, the one with the smallest mass is the

A) electron.
B) proton.
C) neutron.
D) neutrino.

Question 9

The electromagnetic waves emitted by a nucleus are called

A) ultraviolet rays.
B) X-rays.
C) gamma rays.
D) quarks.

Question 10

The atomic number of the nucleus is

A) 4.
B) 5.
C) 9.
D) 13.

Question 11

The nucleus of an atom cannot be said to

A) contain most of the atom's mass.
B) be small in size.
C) be electrically neutral.
D) deflect alpha particles that come near it.

Question 12

The number of protons in the nucleus is

A) 4.
B) 5.
C) 9.
D) 13.

Question 13

The number of neutrons in the nucleus is

A) 4.
B) 5.
C) 9.
D) 13.

Question 14

Of the following particles, the one with the greatest mass is the

A) electron.
B) proton.
C) neutron.
D) neutrino.

Question 15

Which one or more of the following statements is true in general?

A) Alpha particles are more able to penetrate matter than beta particles and gamma rays.
B) Alpha particles are less able to penetrate matter than beta particles and gamma rays.
C) Alpha particles are less able to penetrate matter than beta particles but more able to do so than gamma rays.
D) Alpha particles are more able to penetrate matter than beta particles but less able to do so than gamma rays.

Question 16

The atoms of the isotopes of a given element have the same number of

A) protons.
B) neutrons.
C) nucleons.
D) nuclides.

Question 17

The number of neutrons in a nucleus

A) is less than the number of protons it contains.
B) is the same as the number of protons it contains.
C) is more than the number of protons it contains.
D) Any of the above, depending on the nucleus.

Question 18

The nucleus of a helium atom is called

A) an alpha particle.
B) a beta particle.
C) a gamma ray.
D) a quark.

Question 19

The mass of a positron is

A) equal to the mass of an electron.
B) more than the mass of an electron but less than the mass of a proton.
C) equal to the mass of a proton.
D) more than the mass of a proton.

Question 20

The chemical behavior of an atom is determined by its

A) atomic number.
B) mass number.
C) binding energy.
D) number of isotopes.

Question 21

The moderator in a nuclear reactor

A) slows down neutrons emitted during fission.
B) reduces the production of plutonium.
C) reduces the production of radiation.
D) prevents explosions.

Question 22

Enriched uranium contains

A) more than natural uranium.
B) more than natural uranium.
C) plutonium.
D) tritium.

Question 23

A possible fuel for a fusion reactor is

A)
B)
C) plutonium.
D) tritium.

Question 24

An atomic nucleus has a mass that is

A) less than the total mass of its constituent nucleons.
B) the same as the total mass of its constituent nucleons.
C) more than the total mass of its constituent nucleons.
D) Any of theses choices could be correct, depending on the nucleus.

Question 25

The radiation dosage due to cosmic rays is greatest

A) in orbiting spacecraft.
B) in airplanes at high altitudes.
C) at sea level.
D) underground.

Question 26

A chain reaction does not occur in

A) ordinary nuclear reactors.
B) breeder reactors.
C) fusion reactors.
D) fission nuclear weapons.

Question 27

The most important single source of radiation dosage received by an average person in the United States is

A) medical x-rays
B) nuclear reactors.
C) radon.
D) radium.

Question 28

A nuclear reactor itself does not produce

A) electricity.
B) neutrons.
C) radiation.
D) plutonium.

Question 29

The number of major accidents that have occurred at nuclear power plants is

A) 3.
B) 12.
C) 20.
D) 88.

Question 30

A nucleus with too few neutrons for stability may decay radioactively with the emission of

A) a neutron.
B) a proton.
C) an electron.
D) a positron.

Question 31

As a sample of a radioactive nuclide decays, its half-life

A) decreases.
B) remains the same.
C) increases.
D) Any of these choices could be correct, depending upon the nuclide.

Question 32

Nuclear fission and fusion reactions give off energy because

A) the binding energy per nucleon is least for nuclei of intermediate size.
B) the binding energy per nucleon is greatest for nuclei of intermediate size.
C) they result in the production of neutrons.
D) they result in the production of plutonium.

Question 33

Which of the following is not a unit of energy?

A) joule.
B) kilowatt-hour.
C) ampere-hour.
D) electron volt.

Question 34

By far the most dangerous diagnostic x-rays in medicine are

A) dental x-rays.
B) chest x-rays.
C) CT scans.
D) mammograms.

Question 35

The unit in which atomic masses are usually expressed is the

A) gram.
B) eV.
C) u.
D) quark.

Question 36

Most known nuclides

A) are stable.
B) are radioactive.
C) can undergo fission.
D) have more nuclear mass than the total mass of their constituent nucleons.

Question 37

When a nucleus undergoes radioactive decay, its new mass number is

A) always less than its original mass number.
B) always more than its original mass number.
C) never less than its original mass number.
D) never more than its original mass number.

Question 38

Slightly enriched uranium can be the energy source of which of the following?

A) Nuclear fission reactors.
B) Nuclear fusion reactors.
C) Nuclear weapons.
D) X-rays

Question 39

The sievert is a unit of

A) radioactivity.
B) half-life.
C) particle energy.
D) radiation dosage.

Question 40

If radium and chlorine combine to form radium chloride, the compound is

A) no longer radioactive.
B) half as radioactive as its radium content.
C) as radioactive as its radium content.
D) twice as radioactive as its radium content.

Question 41

The helium isotope undergoes beta decay with the emission of an electron. The product of the decay is

A)
B)
C)
D)

Question 42

The product of the alpha decay of the uranium isotope is

A)
B)
C)
D)

Question 43

The particle that most resembles the proton is the

A) positron.
B) neutron.
C) antiproton.
D) quark.

Question 44

The product of the gamma decay of the strontium isotope is

A)
B)
C)
D)

Question 45

Protons and neutrons are held together to form nuclei by the

A) gravitational interaction.
B) strong interaction.
C) weak interaction.
D) electromagnetic interaction.

Question 46

After 2 h has elapsed, one-sixteenth of the original quantity of a certain radionuclide remains undecayed. The half-life of this radionuclide is

A) 15 min.
B) 30 min.
C) 45 min.
D) 60 min.

Question 47

All known charged particles have electric charges that are multiples of ±e except for

A) electrons.
B) positrons.
C) protons.
D) quarks.

Question 48

When a nucleus of the copper isotope emits a positron, it becomes

A)
B)
C)
D)

Question 49

The strongest of the fundamental interactions is the

A) gravitational interaction.
B) strong interaction.
C) weak interaction.
D) electromagnetic interaction.

Question 50

A proton is annihilated when it interacts with which one or more of the following particles?

A) An electron.
B) A neutron.
C) An antineutron.
D) An antiproton.

Question 51

The number of quarks in a proton or a neutron is

A) 1.
B) 2.
C) 3.
D) 4.

Question 52

The nuclide that decays by electron capture to become is

A)

B)

C)

D)

Question 53

The half-life of tritium is 12.5 years. If we start out with 1 g of tritium, after 25 years there will be

A) no tritium left.
B) 1/4 g of tritium left.
C) 1/2 g of tritium left.
D) a total of 4 g of tritium.

Question 54

The electromagnetic interaction is

A) the fundamental interaction with the shortest range.
B) responsible for the structures of atoms, molecules, liquids, and solids.
C) responsible for holding nucleons together to form nuclei.
D) responsible for radioactive decays.

Question 55

Quarks are not present in

A) electrons.
B) protons.
C) neutrons.
D) hadrons.

Question 56

The process of pair production cannot produce

A) a proton and an antiproton.
B) a neutron and an antineutron.
C) a neutron and a neutrino.
D) an electron and a positron.