IPC chapter 16 test review
The benefits of properly using radioactivity do not include
A complete cure for cancer—yet
chain reaction
A self-sustaining reaction in which the products of one reaction scent stimulate further reaction events
beta particle
An electron (or positron) emitted during the radioactive decay of certain nuclei.
Carbon 14 is a radioactive isotope of carbon those produced in the atmosphere by
Cosmic radiation
equation that most underlies energy released in nuclear event is
E=mc^2
Chain reactions and I fission reactor are caused by
Ejected neutrons
type of force that pushes a nucleus into two parts when fission occurs is
Electric
gamma rays
High-frequency electromagnetic radiation emitted by the nuclei of radioactive atoms.
nuclear fission reactor
Is a high tech way to heat water
Carbon-14 dating
Process of estimating age of once living material by measuring the amount of radioactive isotope of carbon present in material.
critical mass
The minimum mass of a fissionable isotope that provides the number of neutrons needed to sustain a chain reaction
in either a fission event or a fusion event, a quantity that remains unchanged is
The number of nucleons
nuclear fission
The splitting of the nucleus of a heavy atom, such as uranium-235, into two main parts, accompanied by the release of much energy.
Explain how radioactive decay has always warmed Earth from the inside and how nuclear fusion has always warmed Earth from the outside.
Uranium fission produces heat on the inside. Sun has fusion reaction that warms the outside.
when A neutron emits a beta particle it transforms into
a proton
which is the least penetrating in common materials
alpha radiation
describe the three main rays produced by radioactivity? which will penetrate farther into material?
alpha, beta, & gamma. alpha- is combination of two origins and two neutrons easy to shield against because of their relatively large size and double positive change beta- electron ejected from nucleus—fast flying electron gamma- are high frequency electromagnetic radiation emitted by radioactive nuclei. gamma is also the most penetrating
Call contains only minute quantities of radioactive materials, yet more environmental radiation surrounds coal fired power plants than vision power plants. this indicates that the coal fired power plants
are not shielded from radiation
When a chunk of material is broken into smaller pieces, the overall surface area increases. When small pieces are assembled into a larger piece, the combined surface area
decreases
both fission and fusion, energy is released while mass
decreases
When food is exposed to gamma radiation, the food
doesn't become radioactive at all
true/false: a radioactive sample of material is usually slightly cooler than its surroundings
false
true/false: when a heavy nucleus undergoes fission, the fragments of the reaction have more mass than before the fission
false
true/false: when a heavy nucleus undergoes fusion, the result of the reaction has more mass than before the fusion
false
true/false: when an element with a half life of 100 years decays, only half of the original element remains in 500 years
false
which of these rays cannot be deflected by electrical and magnetic means
gamma
which type of natural background radiation most predominates inside high flying airplane: alpha, beta, or gamma?
gamma
Which type of radiation is most penetrating in solid substances
gamma radiation
the element with the most mass per nucleon is
hydrogen
When an element ejects a beta particle the atomic number of that element
increases by 1
in both fission and fusion, mass
is converted into energy
compared with the mass of a uranium atom that undergoes fission, the combined masses of the fission fragments are
less
when energy is released by the process of fission, the total mass of the material after the event is
less
if a uranium nucleus split into three, instead of two equal fragments, the fission fragments would have
less mass per nucleon
Energy can take the form of
light, heat, and mass
the energy released in a fission reaction is found by employing E=mc^2. that is, fine the decrease in mass and
multiplied by the speed of light squared
most of radiation from radioactivity that we daily encounter comes from
nature
thermonuclear fusion
nuclear fusion produced by high temperatures
Most of the radiation from radioactivity in earths biosphere
occurs as natural background radiation
the ultimate source of heat for the water in a geyser is
radioactive decay in earths interior
when an element ejection alpha particle the mass number of resulting element
reduces by four
if a sample of a radioactive isotope has a half life of 1 year, how much of the original sample will be left at the end of the second year? at the end of the third year? at the end of the fourth year?
second year= 1/4 third year= 1/8 fourth year= 1/16
nuclear fusion
the combining of nuclei of light atoms to form heavier nuclei, with the release of much energy
transmutation
the conversation of an atomic nucleus of one element into an atomic nucleus of another element through a loss or gain in the number of protons
alpha particle
the nucleus of a helium atom, which consists of two neutrons and two protons, ejected by certain radioactive elements
radioactivity
the process whereby unstable atomic nuclei break down and emit radiation
half-life
the time required for half the atoms in a sample of a radioactive isotope to decay
When a nucleus of uranium-238 emits an alpha particle, the resulting nucleus is
thorium-234
true/false: carbon-14 is produced in the atmosphere by the incidence of cosmic rays
true
true/false: nearly all the uranium in the world will in the distant future become lead
true
true/false: when an atom emits a beta particle, it becomes a different atom with a higher atomic number
true
true/false: when an atom emits an alpha particle, the resulting atom has less mass and less charge
true
true/false: when any element decays by emitting a beta particle, it becomes an entirely different element
true
when an atom undergoes alpha or beta decay, it
turns into a completely different element
to date the age of a rock formation scientist turn to the radioactivity of
uranium
A certain element in minutes one alpha particle and it products then he met to beta particles in succession. the atomic number of the resulting element is changed by
zero
A certain radioactive element has a half-life of one hour. If you start with 1.00 g sample of the element at noon how much of the same element will be left at 3 PM
0.125 g
are you certain radioactive element has a half-life of two hours. If you start with 1.00 g sample of the element at noon how much of the same element will be left at 4 PM
0.25 g
when the isotope plutonium 239 emits an alpha particle, the atomic mass of the resulting element is
235
a certain radioactive substance has a half life of one hour. if you start 1 gram of material at noon, how much will be left at 3:00 pm? at 4:00 pm?
3:00 pm= .125 g 4:00 pm= .0625 g
The half life of uranium 238 is 4.5 billion years. Compared with the amount of uranium 238 in the earth today only have that amount will exist in
4.5 billion years