CHM112 chapter 24
Which particle will complete the nuclear equation shown correctly? P1530 + ? → Si1430
0, -1 e
The half-life of the isotope 74353574Br is 25.4 minutes. If a 4.0-mg sample is given to a patient, how much of the isotope remains after 90.0 minutes?
0.344 mg
Identify Y correctly in the nuclear equation Y → S1632 + β−10Y → S1632 + β-10. Multiple choice question.
32, 15 P
Which of the following are natural source(s) of background radiation? Select all that apply.
40K Th, U, and Rn 14CO2 Cosmic radiation
Which of the following nuclides is the most stable? The binding energy per nucleon is listed in parentheses.
56Fe (8.8 MeV)
Binding energy per nucleon peaks at what mass number?
60
Calculate the binding energy per nucleon for 235U (mass of 235U atom = 235.043924 amu).
7.591 MeV
Calculate the nuclear binding energy per nucleon for 16O. Mass of 16O = 15.99492 amu; mass of 1H atom = 1.007825 amu; neutron mass = 1.008665 amu; 1 amu = 931.5 MeV.
7.9760 MeV/nucleon
Select the nuclear shorthand that correctly represents the balanced equation Mo4298 + p11 → Tc4398 + n01Mo4298 + p11 → Tc4398 + n01.
98Mo(p,n)98Tc
gray (Gy) rad rem RBE sievert (SV)
Absorption dose corresponding to 1 J of energy per kilogram of body tissue Absorption dose corresponding to 0.01 J of energy per kilogram of body tissue Unit of radiation damage on body tissue found by multiplying the absorbed dose in rads by the RBE Multiplication factor which accounts for the relative damage caused by the radiation Unit of radiation damage on body tissue found by multiplying the absorbed dose in grays by the RBE
Which of the following statements correctly describe the three natural types of radioactive emission? Select all that apply.
An alpha particle has a charge of +2. Alpha particles are the heaviest of the three types of radiation. The symbol β−10β-10 denotes beta radiation.
Which of the following statements correctly defines radioactivity?
An unstable nucleus spontaneously emits radiation.
Which of the following statements correctly describe how human risk from ionizing radiation is assessed? Select all that apply.
Animal studies on mice and dogs Models of risk assessment Hereditary studies on animals and humans Human studies of those accidentally exposed and Japanese atom bomb survivors
What device utilizes an uncontrolled nuclear fission chain reaction?
Atomic bomb
Binding energy per nucleon peaks at a mass number (A) of .
Blank 1: 60, sixty, or 60.0
The most common unit used to express the binding energy of a single nucleus is .
Blank 1: MeV or mega-electron volt
A plot of the number of neutrons (N) on the y-axis vs. the number of protons (Z) on the x-axis for all stable nuclides gives a curve, called the of , which can be used to predict nuclide stability.
Blank 1: band or belt Blank 2: stability
When balancing a nuclear equation, the sum of the Z numbers, representing the for each particle, must be the same for reactants and products. In addition, the total sum of the protons and , given by the number, must be equal for both reactants and products.
Blank 1: charge, charges, protons, or atomic number Blank 2: neutrons Blank 3: A or mass
When an atom is exposed to ionizing radiation it produces a free and a cation. The the energy of the incoming radiation, the greater the number of these charged pairs.
Blank 1: electron, e-, or radical Blank 2: higher, greater, or larger
Nuclear fusion has the potential to supply a large amount of , but it requires extremely high and is not yet practical on Earth.
Blank 1: energy or power Blank 2: temperatures, temperature, heat, or energy
The rate of decay for any large sample of nuclei is found to be equal to kN (where N is the number of nuclei in the sample) and follows -order kinetics. The constant k is characteristic for a specific nucleus.
Blank 1: first or 1st Blank 2: decay or rate
The time taken for half the radioactive nuclei in a sample to decay is called the of the nuclide. This value is characteristic of a specific and is not dependent on the number of nuclei present.
Blank 1: half-life or half life Blank 2: nuclide, nucleus, or isotope Blank 3: initial, starting, total, actual, beginning, or original
The two key factors that determine the stability of a particular nuclide are the ratio of to protons and the total of the nuclide.
Blank 1: neutrons Blank 2: mass
Controlled nuclear fission reactions are used in nuclear plants to generate steam, which turns a turbine attached to a(n) generator.
Blank 1: power Blank 2: electric
During positron emission a(n) is converted into a(n) in the nucleus. This generates a positron, which has a(n) equal to that of the electron but a positive charge.
Blank 1: proton Blank 2: neutron Blank 3: mass
Isotopes of an element have the same number of but a different number of .
Blank 1: protons Blank 2: neutrons
Elements that have a higher atomic number than uranium are termed the elements.
Blank 1: transuranium
Neutrons are useful particles for nuclear bombardment processes because they have charge and are not repelled by a target nucleus. Positively charged particles must have sufficient kinetic to overcome repulsion if they are to be used in this way. This is achieved by using a particle .
Blank 1: zero or no Blank 2: energy or momentum Blank 3: accelerator
What processes are depicted in the illustration? Select all that apply.
Chain reaction Fission
Which of the following nuclides are expected to be unstable? Select all that apply.
Cl1741Cl1741 Am95241Am95241 Mn2546
Select the applications of higher energy ionizing radiation. Select all that apply.
Destruction of microbes Insect control Radiation therapy
Uranium-containing ore Cd and B Be alloy Moderator
Fuel Control rods used to absorb neutrons Reflector that reflects neutrons back to fuel rods Slows neutrons and acts as a coolant
12C 84Kr
Fusion Fission
The danger posed by a radioactive nuclide depends on what factors? Select all that apply.
Half-life of radiation Biochemical behavior Type of radiation
Alpha particle Beta particle Gamma ray
Identical to a helium-4 nucleus High-speed electron emitted from the nucleus Very high-energy photon
How is nuclear fission different from nuclear fusion?
In nuclear fission a heavy nucleus splits into two lighter nuclei while the opposite process occurs in nuclear fusion.
What is the main reason there no definitive assessment of the risk of ionizing radiation on humans?
Intentional exposure to human subjects is forbidden.
Which of the following applications of higher energy ionizing radiation has not been accepted by the U.S. public?
Irradiation of food to kill microorganisms
Which of the following statements correctly define isotopes? Select all that apply.
Isotopes have very similar physical behavior. Isotopes have very similar chemical behavior. Isotopes have the same number of protons.
What is the most common unit used to express nuclear binding energy of a mole of nuclei?
J
What is the most common unit used to express nuclear binding energy of a single nucleus?
MeV
Which of the following are artificial source(s) of background radiation? Select all that apply.
Medical x-rays Nuclear waste disposal CT scans
Which of the following is the correct balanced nuclear equation for the beta decay of magnesium-27?
Mg1227 → AI1327 + β−10
Select the nuclear equation that is represented by the nuclear shorthand 21Ne(n,α)18O
Ne1021 + n01 → O818 + α24Ne1021 + n01 → O818 + α24
What is the ultimate source of nearly all energy on Earth?
Nuclear Fusion
______ are necessary in transmutation reactions because they produce very fast moving particles capable of overcoming the electrostatic repulsions between them and the target nucleus.
Particle accelerators
Which of the following options correctly identify the function of the components of a nuclear reactor? Select all that apply.
Steam operates a turbine electrical generator. Control rods of cadmium or boron capture and control the concentration of neutrons.
Which of the following statements correctly describe how to balance a nuclear equation? Select all that apply.
The total mass number is equal for reactants and products. The total charge for the reactants must equal the total charge for the products. The total number of nucleons is equal for reactants and products.
For which process is the mass change the greatest and why?
There is a mass decrease when nucleons form a nucleus. Nuclear process
H13 Sn50106 Rn86222 W74186
Unstable; N/Z ratio too high Unstable; N/Z ratio too low Unstable; Z > 83 Stable
Some modern accelerators achieve very high energy particle collisions using ______.
both a linear section and a synchrotron section
Atoms are rearranged by the breaking and forming of chemical bonds in a An element or isotope is converted into a different element or isotope in a The energy changes in a nuclear reaction are The energy changes in a chemical reaction are
chemical reaction. nuclear reaction. extremely large. relatively small.
A particle's path is _____ in a synchrotron.
circular
A common unit of radioactivity is the ______, defined as 3.70 x 1010 disintegrations per second, which is the rate of decay of 1 g of radium.
curie (Ci)
A succession of nuclear reactions that begins with an unstable parent nuclide and ends with a stable daughter nuclide is called a ______.
decay series
Ionizing radiation causes an atom or molecule to produce a cation and a free electron, the number of which depends ______ energy of the incoming ionizing radiation.
directly on the
The primary use for nuclear fission in the world today is the generation of _____.
electricity
Lighter stable nuclei (Z ≤ 20) have an ______ number of protons and neutrons, but for nuclei with Z greater than 20, the ratio of N/Z gradually ______ as Z increases.
equal; increases
In nuclear _____ a heavy nucleus splits into two much lighter nuclei, emitting several small particles at the same time. In nuclear _____ the opposite process occurs; two lighter nuclei combine to form a heavier one.
fission; fusion
Correctly order the penetrating power of the different types of emissions from most to least penetrating, with the most penetrating type at the top of the list. Instructions
gamma beta alpha
The penetrating power of nuclear emissions is _____ related to the mass and charge of the radiation.
inversely
The half-life for a particular nuclide is _____ proportional to the decay constant. A substance that has a large value of k will have a _____ t1/2 while a substance with a small value of k will have a _____ t1/2.
inversely; small; large
All nuclear radiation causes chemical changes in surrounding matter. Radiation interacts with matter to produce _____. Select all that apply.
ions electrons radicals
Radioisotopic dating is possible because the half-life of a nuclide ______ and the relative isotope abundances in an object are measurable.
is constant
Which of the following equations correctly expresses the change in the number of radioactive nuclei present over time? Select all that apply.
ln N1/N0 = -kt Nt = N0e-kt ln N0/N1 = kt
The greater the binding energy per nucleon the _____ stable the nucleus.
more
Particle accelerators are necessary in transmutation reactions because they produce very fast moving particles capable of ______ between them and the target nucleus.
overcoming the electrostatic repulsions
A ______ is a radioisotope added to a stable isotope of the same element to monitor the element's distribution as it progresses through a system.
tracer
Pu94244 Xe54153 Cu2955
α decay β- decay e- capture or β+ emission
Nuclear power plants use ______ reactions to produce heat that boils water to steam. The steam then rotates a turbine attached to an electric generator.
controlled fission
Which of the following equations correctly expresses the change in the number of radioactive nuclei present over time?
ln No/Nt = kt
The energy level model of the nucleus describes nucleons residing in levels analogous to the energy level structure for electrons in atoms. Nuclear stability is then attributed to filled nucleon energy levels. The numbers of nucleons that result in this stability are called ______ numbers.
magic
The mass change in a _____ process is much greater than that of a _____ process.
nuclear; chemical
A(n) ______ may be used in chemical analysis to study pathways of a chemical reaction.
radioisotopic tracer
A linear accelerator speeds up a charged particle by sending it through a series of tubes in which the particle is ______ by the tube it is exiting and ______ to the tube it is entering using a source of alternating voltage.
repelled; attracted
A _____ nuclide tends to undergo fusion, whereas a _____ nuclide tends to undergo fission to create more stable products.
small; large
Which of the following is the correct designation for the nuclide Na1124Na1124?
sodium-24
A cyclotron accelerates particles by applying an alternating voltage between two facing D-shaped electrodes placed between large electromagnets, whose magnetic field causes the particles to follow a ______ path.
spiral
Particle accelerators have been primarily used by chemists to ______. Select the best answer.
synthesize transuranium elements
Which of the following correctly relates the half-life to the decay constant for a particular nuclide?
t1/2 = ln2/k
The atomic bomb is different than a nuclear power reactor because it uses a(n) ______ nuclear fission reaction.
uncontrolled
Gy rad rem sv
1 J/kg 0.01 J/kg no. rad x RBE 100 rem
K1942 Xe54128 Np93239 Pb82185
1.21 1.37 1.57 1.26
Which of the following statements correctly describe nuclear reactions? Select all that apply.
A nuclear reaction is accompanied by a measurable change in mass. Protons, neutrons, and electrons are involved in nuclear reactions. Nuclear reactions involve very large energy changes.
Which of the following statements correctly describe the preferred mode of decay for a given nuclide? Select all that apply.
A nuclide with too many protons will undergo e- capture. A nuclide with Z > 83 will undergo α decay. β- decay is typical for nuclides for which the N/Z ratio is too high.
The mass of fissionable material required to achieve a nuclear chain reaction is called the mass.
Blank 1: critical
Which particle or nucleus is required to complete the equation for the following nuclear transmutation reaction correctly? Co2760 + α24 → ? + n01
Cu29/63
Nucleon Nuclide Isotope
Particle found in the nucleus of an atom A nucleus with a specific composition Atom of a particular element that differs in its number of neutrons
Which of the following statements correctly describe a particle denoted by the symbol β10β10? Select all that apply.
The particle has a charge of +1. This particle is a positron.
Which of the following correctly predicts the most likely mode of radioactive decay for the nuclide As3384As3384?
β- decay because the N/Z ratio is too high
Which of the following options correctly describe the process of γ emission from a nuclide? Select all that apply.
γ emission results in a decrease in the energy of the nucleus. γ emission accompanies most other forms of radioactive decay. A nucleus can emit more than one γ photon at a time.
Bequerel (Bq) Curie (Ci) Specific activity
1 d/s 3.70 x 1010 d/s Decay rate per gram
What is the N/Z ratio for the nuclide Cd48114Cd48114?
1.38
The time taken for half the radioactive nuclei in a sample to decay is called the of the nuclide. This value is characteristic of a specific and is not dependent on the number of nuclei present. Listen to the complete question
Blank 1: half-life or half life Blank 2: nuclide, nucleus, or isotope Blank 3: initial, starting, total, actual, beginning, or original
Which of the following statements correctly describe the observed trends in nuclear stability? Select all that apply.
Elements with an even Z have a greater number of stable nuclides. Nuclides that have even numbers of both protons and neutrons are more likely to be stable. Nuclides with filled nucleon energy levels are exceptionally stable.
What is the correct definition of critical mass?
It is the amount of fissionable material that will self-sustain a nuclear chain reaction.
Which of the following options correctly describe the applications of radioactive tracers? Select all that apply.
One advantage of radioactive tracers is that they are easy to detect. 59Fe is used to monitor blood flow. Radioactive 131I is used to monitor thyroid activity.
Analyzing reaction pathways Destruction of cancer tissue
Radioactive tracers Ionizing radiation
Why isn't nuclear fusion a practical energy source at this time?
Reaction temperatures are difficult to maintain.
What particle and nucleus are required to complete the equation for the following nuclear transformation reaction correctly? Cl1735 + n01 → ? + ?
S1635 + p11
Which of the following statements correctly describe the changes occurring during radioactive decay? Select all that apply.
The composition of the nucleus changes during radioactive decay. A nuclide decays to form a new nuclide of lower energy. Excess energy is carried off by the emitted radiation.
Which of the following statements correctly describe the changes that occur during alpha (α) decay of a nuclide? Select all that apply.
The nucleus emits 2 protons and 2 neutrons. The atomic number of the nucleus decreases by 2.
Which of the following statements correctly describe the rate of radioactive decay? Select all that apply.
The rate of decay is proportional to the total number of radioactive nuclei present. Radioactive decay follows first-order kinetics.
What are the key factors that determine the stability of a nuclide? Select all that apply.
The ratio of neutrons to protons in the nucleus The total mass of the nuclide The number of protons in the nucleus
Transuranium elements are those with higher atomic numbers than uranium, produced by ______.
nuclear transmutation
The danger posed by ionizing radiation on living tissue from a radioactive nuclide depends on the nuclide's type of radiation, half-life, and most importantly, ______.
the nuclide's biochemical behavior
Which of the following statements correctly describe the linear particle accelerator? Select all that apply.
A linear accelerator increases the kinetic energy of the particles using an electric field. A particle is repelled by the tube it is exiting and attracted to the tube it is entering, causing it to accelerate.
What is the net effect of electron capture (EC)?
A proton is transformed into a neutron.
How is an atomic bomb different from a nuclear reactor in a power plant?
An atomic bomb uses an uncontrolled nuclear reaction.
A plot of the number of neutrons (N) on the y-axis vs. the number of protons (Z) on the x-axis for all stable nuclides gives a curve, called the of , which can be used to predict nuclide stability. Listen to the complete question
Blank 1: band or belt Blank 2: stability
Nuclear energy is the energy required to break 1 mol of nuclei into their component protons and neutrons.
Blank 1: binding
The neutrons released from the fission of one nucleus collide with other fissionable nuclei and cause them to split, releasing more neutrons, which then collide with more nuclei, and so on. This is an example of a(n) reaction.
Blank 1: chain or nuclear chain
In a synchrotron, a particle's path is
Blank 1: circular
When a parent nuclide undergoes radioactive decay, it forms a(n) nuclide of energy.
Blank 1: daughter or product Blank 2: lower, lesser, or less
A parent nuclide may require several steps to form a stable daughter nuclide. This series of steps is called a(n) , or disintegration series, which usually has a(n) pattern when displayed on a grid.
Blank 1: decay or decay series Blank 2: zigzag, zig-zag, or diagonal
An unstable nucleus exhibits radioactivity; i.e., it spontaneously disintegrates or by emitting particles and/or electromagnetic .
Blank 1: decays, decomposes, deteriorates, or radiates Blank 2: radiation
The generation of is the primary use for nuclear fission in the world today.
Blank 1: electricity or energy
The cyclotron applies the same principles as the linear accelerator but uses to give the particle a path.
Blank 1: electromagnets Blank 2: spiral
Nuclear stability can be explained by postulating that nucleons are arranged in specific levels within the nucleus. A(n) level will result in an exceptionally stable system. The numbers of nucleons that result in this stability are called numbers.
Blank 1: energy Blank 2: filled, full, or complete Blank 3: magic
A change can be induced in a nucleus if it is bombarded with high- particles such as α particles, protons, or neutrons. This general type of reaction is known as nuclear .
Blank 1: energy Blank 2: transmutation
The ultimate source of nearly all energy on Earth is nuclear in the sun.
Blank 1: fusion
Alpha decay is the most common means for a nucleus with a(n) mass number to become more stable. As the nucleus emits an alpha particle, the atomic number decreases by and the mass number decreases by .
Blank 1: high, large, or big Blank 2: 2 or two Blank 3: 4 or four
In an ionization counter, radioactive emissions collide with gas particles, producing and electrons, which can be detected as an electric current. A scintillation counter detects radioactive emissions by their ability to excite atoms and cause them to emit , which in turn creates an electric current through the effect.
Blank 1: ions or cations Blank 2: light or photons Blank 3: photoelectric
In an ionization counter, radioactive emissions collide with gas particles, producing and electrons, which can be detected as an electric current. A scintillation counter detects radioactive emissions by their ability to excite atoms and cause them to emit , which in turn creates an electric current through the effect. Listen to the complete question
Blank 1: ions or cations Blank 2: light or photons Blank 3: photoelectric
Glucose (C6H12O6) is formed from CO2. Chemists were able to use a radioactively carbon atom to trace the pathway of carbon from CO2 to glucose. Radioactive isotopes that are used in this manner are called radioactive .
Blank 1: labeled or tagged Blank 2: tracers
Nuclides are often designated by using the element followed by the number. The nuclide Ca2041Ca2041 would be designated as calcium-.
Blank 1: name or symbol Blank 2: mass Blank 3: 41
During β- decay of a nuclide, a(n) is converted into a(n) in the nucleus of the atom. During this process a high-energy , also called a β particle or β- particle, is expelled from the nucleus.
Blank 1: neutron Blank 2: proton Blank 3: electron or negatron
During β- decay of a nuclide, a(n) is converted into a(n) in the nucleus of the atom. During this process a high-energy , also called a β particle or β- particle, is expelled from the nucleus. Listen to the complete question
Blank 1: neutron Blank 2: proton Blank 3: electron or negatron
Nuclides with too many will tend to undergo β- decay, while nuclides whose N/Z value is too low will decay either by β+ emission or capture. Nuclides with Z > 83 will decay by emitting a(n) particle.
Blank 1: neutrons Blank 2: electron Blank 3: alpha
The protons and neutrons that make up the nucleus of an atom are collectively called . A(n) is a nucleus that has a specific combination of protons and neutrons.
Blank 1: nucleons Blank 2: nuclide
Gamma emission involves the radiation of high-energy γ from an excited nucleus. This type of radiation accompanies most other types of decay. γ rays have no or charge; hence there is change to either A or Z of the nuclide due to γ emission.
Blank 1: photons, rays, particles, or radiation Blank 2: mass Blank 3: no or zero
Gamma emission involves the radiation of high-energy γ from an excited nucleus. This type of radiation accompanies most other types of decay. γ rays have no or charge; hence there is change to either A or Z of the nuclide due to γ emission. Listen to the complete question
Blank 1: photons, rays, particles, or radiation Blank 2: mass Blank 3: no or zero
During positron emission a(n) is converted into a(n) in the nucleus. This generates a positron, which has a(n) equal to that of the electron but a positive charge. Listen to the complete question
Blank 1: proton Blank 2: neutron Blank 3: mass
A radioactive tracer contains a small amount of the isotope and a large amount of the isotope. The tracer acts as a chemical beacon emitting that signals the presence of a particular substance.
Blank 1: radioactive or radio Blank 2: stable or nonradioactive Blank 3: radiation
The age of certain materials and artifacts can be estimated by dating, since many materials naturally contain radioactive isotopes. Each nuclide has its own unique and therefore rate of decay. By comparing the abundance of the isotope to that of its decay products, we can estimate the time elapsed since the beginning of the process.
Blank 1: radioisotope, radioisotopic, radiometric, or radioactive decay Blank 2: half-life, decay constant, or half life
The nucleus is held together by an attractive force called the force, which exists between all nuclear particles and operates only over short distances. Competition between this force and the electrostatic proton-proton determines nuclear stability.
Blank 1: strong or strong nuclear Blank 2: repulsion or repulsions
The nucleus is held together by an attractive force called the force, which exists between all nuclear particles and operates only over short distances. Competition between this force and the electrostatic proton-proton determines nuclear stability. Listen to the complete question
Blank 1: strong or strong nuclear Blank 2: repulsion or repulsions
Which of the following statements correctly describe the observed trends in nuclear stability? Select all that apply.
Competition between strong force and the electrostatic proton-proton repulsion determines nuclear stability. The pairing of spins of like nucleons in nucleon energy levels may result in greater stability. The majority of stable nuclides have both an even number of neutrons and an even numbers of protons.
Which of the following statements correctly describe β-decay of a radioactive nuclide? Select all that apply.
In this type of decay, a neutron is converted to a proton in the nucleus. The atomic number of the nuclide increases by 1. β- decay is also called negatron emission.
Which of the following options describe the problems in the normal use of nuclear power plants? Select all that apply.
Nuclear power plants generate nuclear waste. Nuclear power plants generate thermal pollution.
Electron capture Beta decay Positron emission Alpha decay
Pd46103 + β-10 → Rh45103 Fr87223 → Ra88223 + β-10 Mg1223 → Na1123 + β+10 Bi83212 → TI81208 + α24
Which of the following are application(s) of particle accelerators? Select all that apply.
Producing radioisotopes for medical applications Studying the fundamental nature of matter Synthesis of transuranium elements
What effect does all radiation have on surrounding matter?
Radiation causes the ionization of surrounding matter.
Which of the following statements correctly describe how radiation interacts with matter? Select all that apply.
Radioactive emissions cause electrons to be dislodged from an atom or molecule. All types of radiation cause the ionization of matter. Radiation results in the formation of free radicals.
Which of the following statements correctly describe the applications of radioisotopes in our world? Select all that apply.
Radioactive tracers can be used to study reaction pathways. The flow of materials can be studied using radioactive tracers. Radioactive tracers contain a small amount of radioisotope mixed with the stable isotope.
Select the devices used to measure radioactivity. Select all that apply.
Scintillation counters Ionization counters
Which of the following are included in powerful modern accelerators like the tevatron in Chicago and the Large Hadron Collider near Geneva, Switzerland? Select all that apply.
Synchrotron Linear accelerator
What is nuclear binding energy?
The energy required to break 1 mol of nuclei into individual protons and neutrons.
Which of the following statements correctly describe the half-life of a radioactive nuclide? Select all that apply.
The half-life is the time taken for half the nuclei present in a sample to decay. A nuclide with a long half-life will have a small decay constant k. Two nuclides of the same element frequently have different half-lives.
Which of the following statements correctly describe the observed trends in nuclear stability? Select all that apply.
The majority of stable nuclides have both an even number of neutrons and an even numbers of protons. Competition between strong force and the electrostatic proton-proton repulsion determines nuclear stability. The pairing of spins of like nucleons in nucleon energy levels may result in greater stability.
Which of the following options correctly describe the changes that occur during positron emission? Select all that apply.
The mass number of the nuclide does not change. The process p11→n01+β+10p11→n01+β+10 occurs in the nucleus.
Which of the following statements correctly describe electron capture? Select all that apply.
The net effect is the same as for positron emission. The atomic number decreases by 1. The mass number of the nuclide is unchanged.
Which of the following statements correctly describe the observed trends in nuclear stability? Select all that apply.
The pairing of spins of like nucleons in nucleon energy levels may result in greater stability. Competition between strong force and the electrostatic proton-proton repulsion determines nuclear stability. The majority of stable nuclides have both an even number of neutrons and an even numbers of protons.
Which of the following statements correctly describe the band of stability? Select all that apply.
The plot shows that heavier nuclides require a higher proportion of neutrons to stabilize the nucleus. Any nuclides whose N/Z ratio falls above the band are unstable. This is a plot of N vs. Z for all stable nuclides.
Which of the following is NOT an issue associated with nuclear power plants?
The production of airborne pollutants like greenhouse gases
Which of the following statements correctly describe a nuclear transmutation reaction? Select all that apply.
The products include a new isotope as well as one or more nuclear particles. A change is induced in a nucleus by bombarding it with high-energy particles.
Which is the more destructive species, OH−OH- or ∙OH∙OH? Why?
The radical ∙OH Free radicals are very reactive and will react with any other molecules present.
A sample of wood taken from an ancient tomb shows a radioactivity level of 7.0 counts per minute, whereas a fresh sample of wood shows 15.3 counts per minute. The half-life of C614C614 is 5720 years. Select all the statements that correctly interpret this data.
The sample is approximately 6452 years old. 1.13 half-lives have passed since the wood was living.
X Z A
The symbol for the element or particle The charge of the particle The mass number of the particle
Iodine-131 Oxygen-15 Fluorine-18 Cobalt-60
Used to monitor thyroid gland function Positron-emitter used to assess heart function Positron-emitter used to assess energy metabolism Used in cancer therapy
