Deck 21: Nuclear Chemistry

Question 1

Which of these nuclides is most likely to be radioactive?

A)
B)
C)
D)
E)

Answer 1

Question 2

In the nuclear transmutation represented by ?, what is the product?

A) nitrogen- 16
B) carbon- 12
C) carbon- 14
D) carbon- 16
E) nitrogen- 15

Answer 2

carbon- 14

Question 3

If we start with 1.000 g of cobalt- 60, 0.675 g will remain after 3.00 yr. This means that the half- life of cobalt- 60 is _ _ yr.

A) 3.08
B) 7.65
C) 2.03
D) 5.30
E) 4.44

Answer 3

5.30

Question 4

In the nuclear transmutation represented by ?, what is the product?

A) uranium- 245
B) curium- 242
C) uranium- 242
D) curium- 245
E) uranium- 243

Question 5

The mass of a proton is 1.00728 amu and that of a neutron is 1.00867 amu. What is the binding energy (in J) of a nucleus? (The mass of a cobalt- 60 nucleus is 59.9338 amu.)

A) 8.206 × 10^{- 11}
B) 9.117 × 10^{- 28}
C) 4.940 × 10^{- 13}
D) 2.735 × 10^{- 16}
E) 2.735 × 10^{- 19}

Question 6

The basis for the carbon- 14 dating method is that

A) living tissue will not absorb carbon- 14 but will absorb carbon- 12.
B) carbon- 14 is very unstable and is readily lost from the atmosphere.
C) the amount of carbon- 14 in all objects is the same.
D) the ratio of carbon- 14 to carbon- 12 in the atmosphere is a constant.
E) All of the above are correct.

Question 7

Which type of radioactive decay results in no change in mass number and atomic number for the starting nucleus?

A) electron capture
B) beta
C) positron emission
D) alpha
E) gamma

Question 8

A rock contains 0.313 mg of lead- 206 for each milligram of uranium- 238. The half- life of for the decay of uranium- 238 to lead- 206 is 4.5 × 10⁹ yr. The rock was formed yr ago.

A) 2.00 × 10⁹
B) 1.39 × 10⁹
C) 1.56 × 10⁹
D) 1.41 × 10⁹
E) 1.08 × 10⁹

Question 9

In the nuclear transmutation,, what is the bombarding particle?

A) a phosphorus nucleus
B) a gamma photon
C) an alpha particle
D) a beta particle
E) a proton

Question 10

What is required for a nuclear transmutation to occur?

A) a particle to collide with a nucleus
B) a corrosive environment
C) gamma emission
D) very high temperature
E) spontaneous nuclear decay

Question 11

²¹⁰Pb has a half- life of 22.3 years and decays to produce ²⁰⁶Hg. If you start with 7.50 g of ²¹⁰Pb, how many grams of ²⁰⁶Hg will you have after 17.5 years?

A) 0.0600
B) 3.09
C) 1.71
D) 3.15
E) 4.35

Question 12

At approximately what number of protons, or neutrons, does the 1:
1 ratio of protons to neutrons start to produce unstable nuclei?

A) 30
B) 50
C) 10
D) 80
E) 20

Question 13

If we start with 1.000 g of strontium- 90, 0.908 g will remain after 4.00 yr. This means that the half- life of strontium- 90 is _ yr.

A) 28.8
B) 4.40
C) 41.6
D) 3.63
E) 3.05

Question 14

The mass of a proton is 1.673 × 10^{- 24} g. The mass of a neutron is 1.675 × 10^{- 24} g. The mass of the nucleus of an ⁵⁶Fe atom is 9.289 × 10^{- 23} g. What is the nuclear binding energy (in J) for ⁵⁶Fe?
(c = 3.00 × 10⁸ m/s)

A) 8.36 × 10^{- 9}
B) 7.72 × 10^{- 8}
C) 7.72 × 10^{- 11}
D) 2.57 × 10^{- 16}
E) 6.07 × 10⁶

Question 15

The mass of a proton is 1.00728 amu and that of a neutron is 1.00867 amu. What is the mass defect (in amu) of a ⁶⁰ Ni nucleus? (The mass of a nickel- 60 nucleus is 59.9308 amu.)

A) 0.5449
B) 28.7930
C) 1.2374
D) 1.3066
E) 0.5505

Question 16

In the nuclear transmutation represented by ?, what is the bombarding particle?

A) positron
B) proton
C) alpha particle
D) electron
E) neutron

Question 17

What is emitted in the nuclear transmutation,?

A) a gamma photon
B) a neutron
C) a proton
D) an alpha particle
E) a beta particle

Question 18

What is the missing product from this reaction?

A)
B)
C)
D)
E)

Question 19

Which one of the following can be done to shorten the half- life of the radioactive decay of uranium- 238?

A) heat it
B) freeze it
C) oxidize it to the +2 oxidation state
D) convert it to UF₆
E) none of the above

Question 20

What is the atomic number of a neutron ?

A) 0
B) 3
C) 1
D) 4
E) 2

Question 21

Which one of the following requires a particle accelerator to occur?

A)
B)
C)
D)
E) none of the above

Question 22

Strontium- 90 is a byproduct in nuclear reactors fueled by the radioisotope uranium- 235. The half- life of strontium- 90 is 28.8 yr. What percentage of a strontium- 90 sample remains after 75.0 yr?

A) 16.5
B) 68.1
C) 38.4
D) 2.60
E) 7.40

Question 23

How much energy is produced when 0.082 g of matter is converted to energy?

A) 2.5 × 10⁷
B) 7.4 × 10¹⁸
C) 7.4 × 10¹⁵
D) 2.5 × 10⁴
E) 7.4 × 10¹²

Question 24

The half- life of a radionuclide

A) gets longer with passing time.
B) is constant.
C) gets longer with increased temperature.
D) gets shorter with passing time.
E) gets shorter with increased temperature.

Question 25

Carbon- 11 is used in medical imaging. The half- life of this radioisotope is 20.4 min. What percentage of a sample remains after 60.0 min?

A) 13.0
B) 71.2
C) 34.0
D) 2.94
E) 5.28

Question 26

The half- life of cobalt- 60 is 5.2 yr. How many milligrams of a 2.000- mg sample remains after 6.55 years?

A) 1.588
B) 1.163
C) 0.837
D) 3.23 × 10^{- 15}
E) 4.779

Question 27

In the nuclear transmutation represented by ?, what is the emitted particle?

A) alpha particle
B) electron
C) neutron
D) positron
E) proton

Question 28

In terms of binding energy, what element divides fission and fusion processes?

A) H
B) U
C) He
D) Fe
E) C

Question 29

Bombardment of uranium- 238 with a deuteron (hydrogen- 2) generates neptunium- 237 and
Neutrons.

A) 1
B) 2
C) 3
D) 4
E) 5

Question 30

The carbon- 14 dating method can be used to determine the age of a

A) papyrus scroll.
B) clay pot.
C) flint arrowhead.
D) stone axe head.
E) rock.

Question 31

What type of reaction is known as a thermonuclear reaction?

A) fission
B) fusion
C) neutron emission
D) beta emission
E) transmutation

Question 32

Which one of the following is not true concerning radon?

A) It has been implicated in lung cancer.
B) It is generated as uranium decays.
C) It decays to polonium- 218, an alpha emitter.
D) It decays by alpha emission.
E) It is chemically active in human lungs.

Question 33

The main scientific difficulty in achieving a controlled fusion process is the

A) enormous repulsion between the electrons of atoms being fused.
B) enormous repulsion between nuclei being fused.
C) very large number of gamma rays emitted.
D) very large number of x- rays emitted.
E) very large number of positrons emitted.

Question 34

Which of the following correctly represents the transmutation in which neptunium- 239 is produced via bombardment of uranium- 238 with a neutron?

A)
B)
C)
D)
Е)

Question 35

Atoms with the same atomic number and different mass numbers

A) do not exist.
B) are resonance structures.
C) are allotropes
D) are isotopes.
E) are isomers.

Question 36

Which one of the following processes results in an increase in the atomic number?

A) positron emission
B) gamma emission
C) alpha emission
D) corrosion
E) beta emission

Question 37

Which one of the following is true?

A) All spontaneous nuclear reactions are exothermic.
B) All spontaneous nuclear reactions are endothermic.
C) Some spontaneous nuclear reactions are exothermic.
D) There is no relationship between exothermicity and spontaneity in nuclear reactions.
E) Some spontaneous nuclear reactions are endothermic.

Question 38

How many radioactive decay series exist in nature?

A) 0
B) 1
C) 2
D) 3
E) 10

Question 39

Which one of the following is a correct representation of a beta particle?

A)
B)
C)
D)
E)

Question 40

Which one of the following forms of radiation can penetrate the deepest into body tissue?

A) beta
B) proton
C) alpha
D) positron
E) gamma

Question 41

All atoms of a given element have the same

A) atomic mass.
B) atomic number.
C) number of nucleons.
D) number of neutrons.
E) mass number.

Question 42

The half- life for beta decay of strontium- 90 is 28.8 years. A milk sample is found to contain 10.3 ppm strontium- 90. How many years would pass before the strontium- 90 concentration would drop to 1.0 ppm?

A) 92.3
B) 0.112
C) 96.9
D) 131
E) 186

Question 43

When two atoms of ²H are fused to form one atom of ⁴He, the total energy evolved is
3)83 × 10^{- 12} J. What is the total change in mass (in kg) for this reaction? (C = 3.00 × 10⁸ m/s)

A) 1.28 × 10^{- 17}
B) 4.26 × 10^{- 26}
C) 1.15
D) 4.26 × 10^{- 29}
E) 3.45 × 10⁸

Question 44

Which of the following correctly represents the transmutation in which a curium- 242 nucleus is bombarded with an alpha particle to produce a californium- 245 nucleus?

A)
B)
C)
D)
E)

Question 45

Which one of the following devices converts radioactive emissions to light for detection?

A) photographic film
B) Geiger counter
C) scintillation counter
D) none of the above
E) radiotracer

Question 46

The curie is a measure of the

A) number of alpha particles emitted by exactly one gram of a radioactive substance.
B) total energy absorbed by an object exposed to a radioactive source.
C) lethal threshold for radiation exposure.
D) number of disintegrations per second of a radioactive substance.
E) None of the above is correct.

Question 47

What is a phosphor?

A) a bioluminescent substance
B) an alkali metal phosphide
C) a substance that thermally reduces to phosphorus
D) an oxide of phosphorus
E) a substance that emits light when excited by radiation

Question 48

What exposure level to radiation is fatal to most humans?

A) 100 rem
B) 200 rem
C) 600 rem
D) 300 rem
E) 1000 rem

Question 49

Of the following processes, which one changes the atomic number?

A) electron capture
B) positron emission
C) alpha emission
D) beta emission
E) All of these processes change the atomic numbers.

Question 50

What is the half- life (in min) of this radionuclide?

A) 44.64
B) 30.9
C) 0.0324
D) 0.0224
E) 0.0242

Question 51

Atoms containing radioactive nuclei are called

A) radioisotopes.
B) nuclides.
C) radionuclides.
D) nucleons.
E) radioisophores.

Question 52

Alpha decay produces a new nucleus whose than those respectively of the original nucleus.

A) atomic number is 2 more and mass number is 4 more
B) atomic number is 2 less and mass number is 4 less
C) atomic number is 2 more and mass number is 2 less
D) atomic number is 2 less and mass number is 2 less
E) atomic number is 1 less and mass number is 2 less

Question 53

Which one of the following is used as a radiotracer to study blood?

A) iodine- 131
B) phosphorus- 32
C) iron- 59
D) sodium- 23
E) technetium- 99

Question 54

What are the "dees" ion a particle accelerator?

A) targets
B) electrodes
C) magnets
D) vibration places
E) transmutated bees

Question 55

A freshly prepared sample of curium- 243 undergoes 3312 disintegrations per second. After 6.00 yr, the activity of the sample declines to 2755 disintegrations per second. The half- life of curium- 243 is Yr.

A) 0.765
B) 32.6
C) 7.21
D) 4.99
E) 22.6

Question 56

What happens to the mass number and the atomic number of an element when it emits gamma radiation?

A) The mass number and atomic numbers remain unchanged.
B) The mass number remains unchanged while the atomic number decreases by one.
C) The mass number decreases by four and the atomic number decreases by two.
D) The mass number remains unchanged while the atomic number increases by one.
E) The mass number increases by four and the atomic number increases by two.

Question 57

What happens to the mass number and the atomic number of an element when it undergoes beta decay?

A) Neither the mass number nor the atomic number change.
B) The mass number decreases by 4 and the atomic number decreases by 2.
C) The mass number increases by 2 and the atomic number increases by 1.
D) The mass number does not change and the atomic number increases by 1.
E) The mass number does not change and the atomic number decreases by 2.

Question 58

What is the rate constant (in min^{- 1}) for the decay of this radionuclide?

A) 0.0242
B) 30.9
C) 0.0224
D) 44.64
E) 0.0324

Question 59

The mass of a proton is 1.00728 amu and that of a neutron is 1.00867 amu. What is the binding energy per nucleon (in J) of a nucleus? (The mass of a cobalt- 60 nucleus is 59.9338 amu.)

A) 7.009 × 10^{- 14}
B) 2.487 × 10^{- 12}
C) 1.368 × 10^{- 12}
D) 9.432 × 10^{- 13}
E) 3.039 × 10^{- 12}

Question 60

Carbon- 11 decays by positron emission:

The decay occurs with a release of 2.87 × 10¹¹ J per mole of carbon- 11. When 4.00 g of carbon- 11 undergoes this radioactive decay, _ _ g of mass is converted to energy.

A) 1.28 × 10^{- 2}
B) 1.16 × 10^{- 3}
C) 3.48 × 10⁵
D) 1.16 × 10^{- 6}
E) 8.62 × 10²

Question 61

Carbon- 11, fluorine- 18, oxygen- 15 and nitrogen- 13 are all used in the clinical diagnostic technique known as _ .

Question 62

Conversion of one nucleus into another was first demonstrated in 1919 by .

Question 63

_____________discovered radioactivity.

Question 64

What happens to the atomic mass number and the atomic number of a radioisotope when it undergoes alpha emission?

Question 65

High speed electrons emitted by an unstable nucleus are _ .

Question 66

The major type of cancer caused by radiation is .

Question 67

The only element with no neutrons is .

Question 68

Control rods in a nuclear reactor are composed of boron and .

Question 69

The beta decay of cesium- 137 has a half- life of 30 years. How many years must pass to reduce a 25 mg sample of cesium 137 to 8.7 mg?

A) 52
B) 50
C) 32
D) 3.2
E) 46

Question 70

What happens in the nucleus of an atom that undergoes positron emission?

Question 71

Cesium- 137 undergoes beta decay and has a half- life of 30 years. How many beta particles are emitted by a 14.0- g sample of cesium- 137 in three minutes?

A) 8.1 × 10¹⁵
B) 6.2 × 10²²
C) 6.1 × 10¹³
D) 8.4 × 10¹⁵
E) 1.3 × 10^{- 8}

Question 72

⁰ e represents _.
- 1

Question 73

What was the purpose of the Manhattan project?

Question 74

When living tissue is irradiated most of the energy is absorbed by .

Question 75

Potassium- 40 decays to argon- 40 with a half- life of 1.27 × 10⁹ yr. The age of a mineral sample that has a mass ratio of ⁴⁰Ar to ⁴⁰K of 0.812 is _ _ yr.

A) 1.09 × 10⁹
B) 1.56 × 10⁹
C) 1.02 × 10⁹
D) 7.55 × 10⁸
E) 1.47 × 10⁹

Question 76

Stable nuclei with low atomic numbers, up to 20, have a neutron to proton ratio of approximately .

Question 77

The relative biological effectiveness (RB
E) values of beta rays, gamma rays, and alpha rays are, respectively

Question 78

Radioactive seeds that are implanted into a tumor are coated with to stop alpha and beta ray penetration.

Question 79

The half- life for the beta decay of potassium- 40 is 1.3 × 10⁹ years. What is the rate constant for this decay?

Question 80

What isotope of what element is produced if krypton- 81 undergoes beta decay?