Deck 33: Atomic Nucleus and Radioactivity

Question 1

When a nucleus emits a beta particle,its atomic number

A)remains constant,but its mass number changes.
B)remains constant,and so does its mass number.
C)changes,but its mass number remains constant.
D)changes,and so does its mass number.
E)none of these

Answer 1

changes,but its mass number remains constant.

Question 2

X-rays are similar to

A)alpha rays.
B)beta rays.
C)gamma rays.
D)all of these
E)none of these

Answer 2

gamma rays.

Question 3

The mass of an atomic nucleon is nearly

A)twice the mass of an electron.
B)four times the mass of an electron.
C)a thousand times the mass of an electron.
D)two thousand times the mass of an electron.

Answer 3

two thousand times the mass of an electron.

Question 4

Which radiation has no electric charge associated with it?

A)alpha rays
B)beta rays
C)gamma rays
D)all of these
E)none of these

Question 5

The half-life on an isotope is one day.At the end of three days,how much of the isotope remains?

A)none
B)one-half
C)one-quarter
D)one-eighth
E)none of these

Question 6

The half-life of an isotope is one day.At the end of two days the amount that remains is

A)none.
B)one-half.
C)one-quarter.
D)one-eighth.
E)none of these

Question 7

The half-life of a radioactive substance is INDEPENDENT of

A)the number (if large enough)of atoms in the substance.
B)whether the substance exists in an elementary state or in a compound.
C)the temperature of the substance.
D)the age of the substance.
E)all of these

Question 8

The sources of X-rays and gamma rays,respectively,are

A)electron clouds and the atomic nucleus.
B)the atomic nucleus and electron clouds.
C)both electron clouds.
D)both the atomic nucleus.
E)none of these

Question 9

An atom with an imbalance of electrons to protons is

A)a hadron.
B)a baryon.
C)an ion.
D)an isotope.
E)none of these

Question 10

Different isotopes of an element have different numbers of

A)protons.
B)hadrons.
C)photons.
D)neutrons.
E)none of these

Question 11

A nucleon is either

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

Question 12

The atomic mass number of an element is the same as the number of its

A)protons.
B)neutrons.
C)nucleons.
D)none of these

Question 13

Deuterium and tritium are both

A)forms of hydrogen.
B)isotopes of the same element.
C)both of these
D)neither of these

Question 14

Generally speaking,the larger a nucleus is,the greater its

A)stability.
B)instability.
C)neither stability nor instability

Question 15

Both X-rays and gamma rays are emitted from

A)different parts of the atom.
B)a variety of certain atomic nuclei.

Question 16

Once an alpha particle is outside the nucleus it is

A)free to wander about the nucleus.
B)quickly bound to a neighboring nucleus.
C)electrostatically repelled.
D)radioactive.

Question 17

A quark is

A)an elementary particle.
B)a building block of nucleons.
C)a building block of hadrons.
D)all of these
E)none of these

Question 18

Electric forces within an atomic nucleus tend to

A)hold it together.
B)push it apart.
C)neither of these

Question 19

The atomic number of an element is the same as the number of its

A)protons.
B)neutrons.
C)nucleons.
D)neither of these

Question 20

X-rays may be regarded as

A)high frequency sound waves.
B)high frequency radio waves.
C)both of these
D)none of these

Question 21

When an alpha particle is ejected from a nucleus,the nucleus then has less

A)mass.
B)charge.
C)both of these
D)neither of these

Question 22

The amount of radiation we personally encounter that originates in the Earth's and the atmosphere's natural background is

A)a trace amount.
B)about a quarter.
C)about half.
D)more than half.

Question 23

All deposits of natural uranium contain appreciable amounts of

A)iron.
B)lead.
C)gold.
D)all of these
E)none of these particularly

Question 24

When a gamma ray is emitted by a nucleus,the nucleus then has less

A)energy.
B)charge.
C)both of these
D)neither of these

Question 25

When an element undergoes nuclear transmutation,the result is a completely different

A)isotope of the same element.
B)ion of the same element.
C)element.

Question 26

Carbon dating requires that the object being tested contain

A)organic material.
B)inorganic material.
C)charcoal.
D)sugar molecules.
E)none of these

Question 27

When a beta particle is ejected from a nucleus,the nucleus then has slightly

A)greater mass and charge.
B)greater mass and smaller charge.
C)smaller mass and significantly greater charge.
D)smaller charge and significantly greater mass.

Question 28

When a beta particle is ejected from a nucleus,the nucleus then has a greater

A)mass.
B)charge.
C)both of these
D)neither of these

Question 29

The origin of cosmic rays is the

A)Earth.
B)clouds.
C)sun.
D)cosmos.
E)none of these

Question 30

The source of the Earth's natural heat is

A)molten-hot lava.
B)pressure on the Earth's interior.
C)radioactive decay in the Earth's core.
D)solar energy in the form of fossil fuels.

Question 31

Pure elements can be transformed into entirely different elements.This statement at the present time is

Question 32

There is a greater proportion of carbon 14 in

A)new bones.
B)old bones.
C)same in each

Question 33

The fate of the world's uranium supply is to eventually become

A)alpha and beta particles.
B)iron.
C)lead.

Question 34

The high temperature of the Earth's interior is due mostly to

A)great internal pressure.
B)friction,as plates move past one another.
C)the Earth's natural heat.
D)radioactivity.

Question 35

The most harmful radiations are those that

A)kill living cells.
B)damage living cells.

Question 36

When a gamma ray is emitted by a nucleus,the nucleus then has appreciably less

A)mass.
B)charge.
C)both of these
D)neither of these

Question 37

Most of the radioactivity we personally encounter comes from

A)fallout from past and present testing of nuclear weapons.
B)nuclear power plants.
C)medical X rays.
D)the natural environment.

Question 38

Carbon 14 is produced in the atmosphere principally by

A)plants and animals.
B)cosmic-ray bombardment.
C)nitrogen bombardment.
D)photosynthesis.
E)none of these

Question 39

Which of the following isotopes is radioactive?

A)Carbon-12
B)Carbon-14
C)Both are radioactive.
D)Neither is radioactive in nature.

Question 40

The operation of a cloud chamber relies on

A)magnetization.
B)evaporation.
C)acceleration.
D)polarization.
E)condensation.

Question 41

When a nucleus emits a beta particle,its atomic number

A)increases by 1.
B)decreases by 1.
C)increases by 2.
D)decreases by 2.
E)none of these

Question 42

A gram of radioactive material has a half-life of one year.After 4 years,how much radioactive material will be left?

A)0 g
B)1/2 g
C)1/4 g
D)1/8 g
E)none of these

Question 43

Which experiences the least electrical force in an electric field?

A)alpha particle
B)beta particle
C)electron
D)gamma ray
E)All experience the same force.

Question 44

A sample of relatively active radioactive material is somewhat

A)warmer than the environment.
B)cooler than the environment.
C)neither really

Question 45

When a nucleus emits a positron,its atomic number

A)increases by 1.
B)decreases by 1.
C)doesn't change.

Question 46

The end result of radioactive decay can be a different

A)isotope.
B)element.
C)atom.
D)all of these
E)none of these

Question 47

When the hydrogen isotope tritium-3 emits a beta particle,it becomes an isotope of

A)hydrogen.
B)helium.
C)lithium.
D)carbon.
E)none of these

Question 48

The helium in a child's balloon is composed of

A)alpha-particle remnants of previous radioactive processes.
B)former beta particles.
C)both of these
D)none of these

Question 49

An element will decay to an element with higher atomic number in the periodic table if it emits

A)a beta particle.
B)a gamma ray.
C)a proton.
D)an alpha particle.
E)none of these

Question 50

Artificially induced radioactive elements generally have

A)long half-lives.
B)short half-lives.

Question 51

Radioactivity in the world is something

A)relatively new.
B)as old as the world itself.

Question 52

When thorium (A = 90)emits a beta particle,the resulting nucleus has atomic number

A)88.
B)89.
C)90.
D)92.
E)none of these

Question 53

Which experiences the greatest electrical force in an electric field?

A)alpha particle
B)beta particle
C)electron
D)gamma ray
E)All experience the same force.

Question 54

The half-lives of elements beyond uranium are too short for these elements to occur in natural deposits.But elements below uranium that have equally short half-lives do occur in natural deposits.This is because they are

A)the small leftover of huge abundances when the Earth formed.
B)subdued and preserved by pressures beneath the Earth.
C)bound with longer-living elements.
D)the products of uranium decay.

Question 55

In order for an atom to decay to an element which is one greater in atomic number,it can emit

A)one alpha particle and 3 beta particles.
B)one positron and 2 beta particles.
C)one beta particle.
D)all of these
E)none of these

Question 56

In bubble chambers,charged particles move in spirals because

A)the magnetic field decreases.
B)the electric charge decreases.
C)the electric charge increases.
D)of perspective and parallax.
E)of energy dissipation.

Question 57

Which body is heated in its interior by nuclear processes?

A)the sun
B)the Earth
C)both
D)neither

Question 58

It's impossible for a hydrogen atom to emit an alpha particle.

Question 59

When radium (A = 88)emits an alpha particle,the resulting nucleus has atomic number

A)86.
B)88.
C)90.
D)92.
E)none of these

Question 60

If an alpha particle and a beta particle have the same energy,which particle will penetrate farther into an object?

A)alpha particle
B)beta particle
C)They both penetrate the same distance.

Question 61

A device that is used primarily to detect nuclear radiation is a

A)synchrotron.
B)linear accelerator.
C)cyclotron.
D)All of the above choices are correct.
E)None of the above choices are correct.

Question 62

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

A)716 years.
B)11,500 years.
C)17,200 years.
D)22,900 years.
E)46,000 years.

Question 63

An element emits 1 alpha particle,1 positron,and 3 beta particles.Its atomic number

A)decreases by 2.
B)decreases by 1.
C)stays the same.
D)increases by 1.
E)increases by 2.

Question 64

A certain radioactive isotope placed near a Geiger counter registers 120 counts per minute.If the half-life of the isotope is one day,what will the count rate be at the end of four days?

A)30 counts/min
B)15 counts/min
C)10 counts/min
D)7)5 counts/min
E)5 counts/min

Question 65

A certain radioactive isotope placed near a Geiger counter registers 160 counts per second.Eight hours later,the counter registers 10 counts per second.What is the half-life of the isotope?

A)8 hours
B)6 hours
C)4 hours
D)2 hours
E)none of these

Question 66

A Geiger counter placed 1 meter from a point source of radiation registers 100 counts per second.If the Geiger counter is moved closer - to 0.5 meter from the source - what will the count rate be?

A)25 counts/s
B)50 counts/s
C)100 counts/s
D)200 counts/s
E)400 counts/s

Question 67

A magnetic field is applied to a cloud chamber to

A)attract electrons.
B)repel electrons.
C)attract protons.
D)repel protons.
E)None of the above choices are correct.

Question 68

A device that could be used to give a positively charged particle enough kinetic energy to penetrate the nucleus of an atom is a

A)streamer chamber.
B)spark chamber.
C)bubble chamber.
D)cloud chamber.
E)None of the above choices are correct.