Deck 22: Nuclear Chemistry

Question 1

If the mass of one neutron is 1.00866 amu,the mass of one proton is 1.00728 amu,and the mass of ¹⁴C nucleus is 13.99995 amu,calculate the binding energy for the ¹⁴C nucleus.

A)9)92 × 10⁹ kJ/mol
B)1)02 × 10¹⁰ kJ/mol
C)5)54 × 10¹¹ kJ/mol
D)5)95 × 10¹¹ kJ/mol

Answer 1

1)02 × 10¹⁰ kJ/mol

Question 2

Which of the following isotopes is the least stable?

A)(⁷Be,5.37 MeV/nucleon)
B)(²³Na,8.11 MeV/nucleon)
C)(⁹⁴Zr,8.67 MeV/nucleon)
D)(²⁴⁰Pu,7.26 MeV/nucleon)

Answer 2

(⁷Be,5.37 MeV/nucleon)

Question 3

Which of the following is not an advantage of fusion reactions over fission reactions for power generation?

A)cheap and plentiful fuel
B)ease of reaction initiation
C)Fusion products are non-polluting.
D)Fusion products are nonradioactive.

Answer 3

ease of reaction initiation

Question 4

The total binding energies for ³He,⁴He,and ⁶He are 7.72 MeV,28.29 MeV,and 29.26 MeV respectively.Arrange the 3 isotopes in increasing order of binding energy per nucleon.

A)(³He < ⁴He < ⁶He)
B)(⁶He < ⁴He < ³He)
C)(⁴He < ³He < ⁶He)
D)(³He < ⁶He < ⁴He)

Question 5

Which of the following isotopes is the most stable?

A)(⁶He,4.89 MeV/nucleon)
B)(²⁰Ne,8.03 MeV/nucleon)
C)(²⁸Si,8.44 MeV/nucleon)
D)(²³²Th,7.62 MeV/nucleon)

Question 6

Mass defect is the mass lost when

A)an atom is formed from individual protons,neutrons,and electrons.
B)a nucleus is formed from individual protons and neutrons.
C)electrons are removed from an atom.
D)electrons are added to an atom.

Question 7

How much energy is released for alpha decay of ²³⁶U? The masses of ⁴He,²³²Th,and ²³⁶U are 4.002604,232.038124,and 236.045637 amu,respectively.

A)1)473 × 10⁸ kJ/mol
B)4)418 × 10⁸ kJ/mol
C)4)909 × 10⁸ kJ/mol
D)7)209 × 10⁸ kJ/mol

Question 8

The sum of the masses of the protons and neutrons in a given nucleus minus the mass of that nucleus is always

A)negative.
B)positive.
C)temperature dependent.
D)zero.

Question 9

Breaking a chemical bond requires approximately 10² kJ/mol of energy.What is closest to the order of magnitude of the energy required to split a nucleus in to its individual protons and neutrons?

A)10³ kJ/mol
B)10⁴ kJ/mol
C)10⁸ kJ/mol
D)10¹⁰ kJ/mol

Question 10

Calculate the mass defect for the formation of phosphorus-31.The mass of a phosphorus-31 nucleus is 30.973765 amu.The masses of a proton and a neutron are 1.00728 and 1.00866 amu,respectively.

A)0)13015 amu
B)0)15404 amu
C)0)27261 amu
D)0)27399 amu

Question 11

If the mass of one neutron is 1.00866 amu,the mass of one proton is 1.00728 amu,and the mass of ¹²C nucleus is 11.99671 amu,calculate the binding energy for the ¹²C nucleus.

A)8)90 × 10⁹ kJ/mol
B)8)90 × 10¹² kJ/mol
C)1)10 × 10¹⁵ kJ/mol
D)1)10 × 10¹⁸ kJ/mol

Question 12

The binding energy is defined as

A)the amount of energy absorbed when electrons are added to an ion.
B)the amount of energy absorbed when protons and neutrons form a nucleus.
C)the amount of energy released when electrons are removed from the atom.
D)the amount of energy required to break apart a nucleus into individual protons and neutrons.

Question 13

Elements with ________ atomic mass are best possible candidates for a fusion reaction.

A)very low
B)moderate
C)moderate to heavy
D)very heavy

Question 14

Which does not apply to a nuclear fusion reaction?

A)Atoms of one element cannot be converted to atoms of another element.
B)Energy is conserved.
C)Matter is conserved.
D)None of these apply to a nuclear fusion reaction.

Question 15

Elements with ________ atomic mass are best possible candidates for a fission reaction.

A)very low
B)moderate
C)moderate to heavy
D)very heavy

Question 16

A binding energy curve is a plot of binding energy per nucleon versus atomic number.In what region of the binding energy curve are the most stable elements found?

A)in the lower left region (low atomic mass)
B)in the central top region (moderate atomic mass)
C)in the lower right region (heavy atomic mass)
D)binding energy is not dependent on atomic mass

Question 17

Four heavy elements (A,B,C,and D)will fission when bombarded by neutrons.In addition to fissioning into two smaller elements,A also gives off a beta particle,B gives off gamma rays,C gives off neutrons,and D gives off alpha particles.Which element would make a possible fuel for a nuclear reactor?

A)element A
B)element B
C)element C
D)element D

Question 18

Which reaction is expected to release the greatest amount of energy?

A)2 H → H₂
B) + →
C) + → + + 2 ¹n
D) + → + + 3

Question 19

Relative to the amount of energy released in a typical chemical reaction,the amount of energy released in a typical fission reaction is about

A)the same.
B)10 times greater.
C)10⁸ times greater
D)10¹⁰ times greater

Question 20

What is the mass change in grams for the reaction 2 NO₂(g) $\rarr$ N₂O₄(g)? The enthalpy for the reaction is -57.2 kJ.

A)-6.36 × 10^-13 g
B)-6.36 × 10^-10 g
C)-1.91 × 10^-7 g
D)-1.91 × 10^-4 g

Question 21

The masses of ⁴He,⁶Li,and ¹⁰B are 4.0015,6.0135,and 10.0102 amu respectively.The fission of a boron-10 nucleus into He-4 and Li-6 would

A)absorb energy.
B)evolve energy.
C)result in no energy change.
D)Need more information

Question 22

The nuclear transmutation reaction that leads to the synthesis of plutonium-241 is shown below.What is the identity of the α-particle bombardment target in this reaction?
? +
→
+

A)
B)
C)
D)

Question 23

The first transuranium element was synthesized by bombarding
With neutrons.After capturing one neutron,the resulting nuclide was unstable and decayed by beta emission.What was the product of these two nuclear reactions?

A)
B)
C)
D)

Question 24

Nitrogen-14 (14.003074 amu)is synthesized in the sun by fusion of ¹³C (13.003355 amu)and ¹H (1.007825 amu).How much energy is released in this nuclear reaction?

A)2)432 × 10⁶ kJ/mol
B)7)295 × 10⁸ kJ/mol
C)9)141 × 10¹⁰ kJ/mol
D)1)807 × 10¹¹ kJ/mol

Question 25

What does the term "critical mass" mean? It is the

A)amount of fissionable material which will self-sustain a nuclear chain reaction.
B)difference between mass of individual protons and neutrons and the mass of the nucleus.
C)energy which holds the nucleus together.
D)mass of fuel in a nuclear reactor core.

Question 26

Which one of the following instruments would be the least suitable for detecting particles given off in radioactive decay?

A)electron microsope
B)Geiger counter
C)photographic film
D)scintillation counter

Question 27

Which ionizing radiation has the greatest energy?

A)α
B)β
C)γ
D)χ

Question 28

A shorthand way of writing transmutation equations is to show the bombarding particle and the subsequent emitted particle in parentheses.Which particle is produced by


(p,α)?

A)
B)
C)
D)

Question 29

What mass percent of ²³⁵U (the fissionable isotope)is used in the fuel in nuclear power plants?

A)3%
B)14%
C)27%
D)83%

Question 30

Oxygen-16 (15.994915 amu)is synthesized in the sun by fusion of ¹²C (12.000000 amu)and ⁴He (4.00260 amu).How much energy is released in this nuclear reaction?

A)2)48 × 10³ kJ/mol
B)2)30 × 10⁶ kJ/mol
C)6)92 × 10⁸ kJ/mol
D)7)20 × 10¹¹ kJ/mol

Question 31

In fusion reactions to make superheavy elements,energy is required to bring the two nuclei together and to form additional mass.How much energy must be converted into mass for the alpha bombardment of ²⁵³Es to form ²⁵⁷Md? (The isotopic masses are ²⁵³Es = 253.08294 amu,⁴He = 4.00260 amu,²⁵⁷Md = 257.09558 amu. )

A)3)01 × 10⁶ kJ/mol
B)9)04 × 10⁸ kJ/mol
C)3)59 × 10¹¹ kJ/mol
D)7)21 × 10¹¹ kJ/mol

Question 32

Radiation is detected by its ________ properties.

A)gravitational
B)ionizing
C)kinetic
D)thermal

Question 33

When
Is formed by bombardment of
,what particle(s)was (were)used for the bombardment?

A)one α
B)two β-
C)4 neutrons
D)2 protons

Question 34

A curie is:

A)the amount of sample that undergoes 1 disintegration per second.
B)the amount of sample that undergoes 3.7 × 10¹⁰ disintegrations per second.
C)the amount of tissue damage done by radiation.
D)equal to 0.01 J of energy absorbed per kilogram of tissue.

Question 35

A sievert is:

A)the amount of sample that undergoes 1 disintegration per second.
B)the amount of sample that undergoes 3.7 × 10¹⁰ disintegrations per second.
C)the amount of tissue damage done by radiation.
D)equal to 0.01 J of energy absorbed per kilogram of tissue.

Question 36

A becquerel is:

A)the amount of sample that undergoes 1 disintegration per second.
B)the amount of sample that undergoes 3.7 × 10¹⁰ disintegrations per second.
C)the amount of tissue damage done by radiation.
D)equal to 0.01 J of energy absorbed per kilogram of tissue.

Question 37

A shorthand way of writing transmutation equations is to show the bombarding particle and the subsequent emitted particle in parentheses.Which of the following equations shows the balanced nuclear reaction for
(n,α)?

A) + → +
B) + → +
C) + → +
D) + → +

Question 38

Which one of the following is most penetrating?

A)alpha particles
B)beta particles
C)gamma rays
D)positrons

Question 39

Which of the following reactions correctly shows the transmutation of an element by neutron absorption followed by beta emission?

A) + → +
B) + → +
C) + → +
D) + → +

Question 40

What is the missing product of the nuclear reaction?
+
→ ? +

A)α
B)β+
C)β-
D)n

Question 41

A few sheets of ordinary paper can form an effective shield against what type of radiation?

A)alpha particles
B)cosmic rays
C)gamma rays
D)neutrons

Question 42

A small block of wood or heavy clothing can form an effective shield against what type of radiation?

A)beta particles
B)cosmic rays
C)gamma rays
D)neutrons

Question 43

An archeological artifact was subjected to radiocarbon dating.The artifact showed a carbon-14 decay rate of 13.8 disintegrations/min per gram of carbon.Carbon-14 has a half-life of 5715 years,and currently living organisms decay at the rate of 15.3 disintegrations/min per gram of carbon.What is the approximate age of the artifact?

A)257 years old
B)371 years old
C)591 years old
D)851 years old

Question 44

Ionizing radiation having the lowest energy is exhibited by

A)α particles.
B)β particles.
C)γ rays.
D)X-rays

Question 45

Which is more dangerous in terms of short-lived exposure to radiation? One mole of

A)(⁸⁹Sr,β^-,t_1/2 = 50.5 days.)
B)(⁹⁰Sr,β^-,t_1/2 = 28.5 years.)
C)(⁹¹Sr,β^-,t_1/2 = 9.5 hours.)
D)(⁹⁴Sr,β^-,t_1/2 = 74 seconds.)

Question 46

Which unit of radiation is frequently used in medicine to describe the amount of tissue damage caused by a radioactive substance?

A)becquerel
B)curie
C)rad
D)rem

Question 47

Which unit of radiation describes the amount of radiation emitted by a radioactive substance?

A)becquerel
B)gray
C)rad
D)rem

Question 48

Carbon-14,which is present in all living tissue,radioactively decays via a first-order process.A one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per minute.If the half-life for carbon-14 is 5715 years,how old is a wood sample that gives a rate for carbon-14 decay of 3.9 counts per minute?

A)4)6 × 10³ yr
B)6)6 × 10³ yr
C)1)0 × 10⁴ yr
D)2)9 × 10⁴ yr

Question 49

Which type of radiation is not used for medical applications?

A)alpha emission
B)beta emission
C)gamma radiation
D)positron emission

Question 50

The ratio of ²³⁸U to ²⁰⁶Pb is used to date old mineral samples.Each 1.000 g of ²³⁸U that decays eventually produces 0.866 g of ²⁰⁶Pb.If the half-life of ²³⁸U is 4.468 × 10⁹ years,what is the age of a mineral that has a ²³⁸U/²⁰⁶Pb mass ratio of 2.00?

A)2)94 × 10⁹ years
B)3)60 × 10⁹ years
C)3)87 × 10⁹ years
D)4)47 × 10⁹ years

Question 51

What type of shielding can be used to protect against gamma rays?

A)cloth
B)lead
C)wood
D)No shielding is effective against gamma rays.

Question 52

What is the abbreviation used for the curie,a unit used in the measurement of nuclear disintegrations per unit time?

A)Cu
B)Cr
C)Ci
D)Ce

Question 53

Most of the radiation to which people are exposed comes from

A)atmospheric testing of nuclear weapons.
B)emissions from nuclear power plants.
C)medical procedures.
D)natural sources.

Question 54

If a log contains 60.0% of the ¹⁴C present in a living tree,how long has the log been dead? The half-life of ¹⁴C is 5730 years.

A)2290 years
B)3430 years
C)4220 years
D)7560 years

Question 55

Which unit of radiation describes the amount of energy absorbed by a kilogram of tissue exposed to a radiation source?

A)becquerel
B)curie
C)rad
D)rem

Question 56

Which type of radiation source would pose the greatest health risk when used internally for a medical procedure?

A)an alpha emitter,t_1/2 = 6 hours
B)a beta emitter,t_1/2 = 6 hours
C)a beta emitter,t_1/2 = 15 days
D)a gamma emitter,t_1/2 = 6 hours

Question 57

A rad is:

A)the amount of sample that undergoes 1 disintegration per second.
B)the amount of sample that undergoes 3.7 × 10¹⁰ disintegrations per second.
C)the amount of tissue damage done by radiation.
D)equal to 0.01 J of energy absorbed per kilogram of tissue.

Question 58

Radiation is dangerous to organisms because

A)all radionuclides are poisonous.
B)it causes electrolysis of water in the cells.
C)it causes nuclear reactions in the cells.
D)it ionizes molecules in the cells.

Question 59

The effects of ionizing radiation depend on

A)length of exposure to radiation.
B)location of source (internal or external).
C)type and energy of radiation.
D)All of these

Question 60

Which of the following isotopes is not used for medical purposes?

A)(³H)
B)(¹⁴C)
C)(³²P)
D)(⁶⁰Co)

Question 61

Energy is ________ (released,required)in the transmutation reaction shown below.The atomic masses are ⁴⁰Ar (39.9624),¹H (1.0078),⁴⁰K (39.9640),¹n (1.0087).
+
→
+

Question 62

What is needed to balance the nuclear transmutation reaction below? →
+ ?

Question 63

If the age of the Earth is 4.5 billion years and the half-life of ⁴⁰K is 1.26 billion years,what percent of the Earth's original amount of ⁴⁰K remains today?

A)4)2%
B)8)4%
C)12%
D)16%

Question 64

What is needed to balance the nuclear fusion reaction below?
2 → + ?

Question 65

The reaction below releases ________ kJ/mol.The atomic masses are ³He (3.0160),¹H (1.0078),⁴He (4.0026),⁰e (0.0005486).
+
→
+

Question 66

The binding energy for lithium-7 nuclei is 3.79 × 10¹² J/mol.The binding energy per nucleon for lithium-7 nuclei is ________ MeV/nucleon.

Question 67

The mass defect for the chemical reaction shown below is ________ g.
2 F → F₂ E = -159 kJ/mol

Question 68

What is needed to balance the nuclear fission reaction below? + →
+ ? + 2

Question 69

The mass change for the reaction shown below is ________ amu.The atomic masses are ³He (3.0160),⁴He (4.0026),¹H (1.0078).
2
→
+ 2

Question 70

Carbon-14,which is present in all living tissue,radioactively decays via a first-order process.A one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per minute.If the half-life for carbon-14 is 5715 years,how old is a wood sample that gives a rate for carbon-14 decay of 11.9 counts per minute?

A)5)3 × 10² yr
B)7)6 × 10² yr
C)1)1 × 10³ yr
D)9)4 × 10³ yr

Question 71

The mass of a helium-4 nucleus is ________ (greater than,less than,the same as)the sum of the masses of two protons plus two neutrons.

Question 72

The mass defect for the formation of lithium-6 is 0.0343 g/mol.The binding energy for lithium-6 nuclei is ________ kJ/mol.

Question 73

The practical limit for ¹⁴C dating occurs when its activity falls to 0.20% of its original value due to interference in detectors by natural background radiation.If the half-life is 5715 years,what is the maximum age of a sample that can be dated by ¹⁴C without interference?

A)1)3 × 10⁴ years
B)2)9 × 10⁴ years
C)5)1 × 10⁴ years
D)2)9 × 10⁶ years

Question 74

In the transmutation reaction that results in the formation of berkelium-243,shown below,the nucleus that is bombarded by alpha particles is ________.
? + → + 2

Question 75

The loss in mass that occurs when protons and neutrons combine to form a nucleus is called the ________ of the nucleus,and the corresponding energy released during the formation of that nucleus is the ________ that holds the nucleus together.

Question 76

Radium occurs only in uranium ores,typically with an observed Ra/U ratio of 1mg/3kg.Uranium ores normally contain only about 200 ppm of U.How many kilograms of uranium ore must be processed to obtain 1 mg of radium?

A)1700 kg ore
B)15,000 kg ore
C)6)0 × 10⁸ kg ore
D)None of these

Question 77

The two reactions shown below are classified as (1)nuclear ________ and (2)nuclear ________.
(1)
+
→
+
+ 3
(2)
+
→

Question 78

Among the types of radiation,α,β,γ,and X,the one that requires the least amount of protective clothing is ________ radiation.

Question 79

Helium-3,an electron,a neutron,and a proton have masses of 3.016029 amu,5.486 × 10^-4 amu,1.00866 amu,and 1.00728 amu,respectively.The mass defect for the formation of helium-3 is ________ amu or ________ g/mol.

Question 80

Units used for measuring radiation include the becquerel,the curie,the gray,and the sievert,which have the abbreviations ________,________,________,and ________,respectively.