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Chem CH 10
Term | Definition |
---|---|
Radioisotopes | elements consist of a mixture of isotopes, some are unstable |
Radioactivity | the nuclear radiation emitted by an isotope the nuclear radiation emitted spontaneously by an unstable radioactive isotope |
Forms of Radiation | Alpha Particle Beta Particle Gamma Ray Positron |
Alpha Particle | lowest energy of particles/rays |
Alpha Particle equals how many protons and neutrons | 2 protons 2 neutrons |
symbol for Alpha particle | look at notes |
protection for Alpha Particle/Emission | largest of particles heaviest of the particles move slow/ penetrate the least protection: paper, clothing, skin dangerous if ingested |
Beta Particles | fast moving electrons high-energy electrons charge= -1 little mass but great energy can travel several meters pass through paper & 4-5 mm into skin |
protection for Beta Particles | heavy clothing, lab coast, gloves |
Symbol for Beta Particles | look at notes |
Gamma Ray | ways of high-energy radiation released from a radioactive nucleus no mass no charge nucleus undergoes rearrangement travels a great distance; penetrates deeply |
Protection for Gamma Ray | lead or concrete they travel the fastest and readily penetrate body tissue |
Positron | is called an anitparticle of a beta particle, becaue their charges are different by their masses are the same neglible mass charge = +1 positive electron |
Symbol for Positron | look at notes |
Radioactive Decay | process by which an unstable radioactive nucleus emits radiation to become stable forming a nucleus of new composition |
Alpha emitters | radioisotopes that decay by emitting alpha particles |
Alpha emission equation | look at notes |
Beta emitters | radioisotopes that decay by emitting beta particles |
Alpha emitters lose what | 2 protons 2 neutrons |
Beta emitters lose what | 1 protons |
what stays the same in a beta emission/equation & a Positron Emission? | the mass # |
Beta equation | look at notes |
Gamma Emitters | radioisotopes that decay by emitting gamma rays |
how common are gamma emitters | few rarely exist |
gamma emission equation | look at notes |
symbol for gamma ray | look at notes |
what does gamma emission lose | nothing the atomic # and mass # stay the same |
Positron Emission | particle emitted has the same mass as electron but =1 charge |
Positron Emission equation | look at notes |
Transmutation | converts stable radioactive isotopes into unstable ones |
in a transmutation an isotope is bombarded by what? | alpha particles, beta particles, and neutrons |
Transmutation equation | look at notes |
Half-life | the amount of time it takes for a radioactive sample to decay radioactive isotope is the time it takes for 1/2 of the sample to decay |
Long half-life | naturally occurring isotope |
Short half-life | artificially produced |
Half life calculation | look at notes |
Device used to detect radiation | Geiger counter film radiation badge |
units used to measure radiation | Curie (Ci) millicurie (mCi) - disintegrations/seconds |
RAD | radiation absorbed does is the amount of radiation absorbed by one gram of a substance. amount of energy absorbed varies w/ both the nature of the substance and the type of radiation |
Gray | absorbed radiation 1 Gy = 100 rad |
Siverts | 1 SV = 100 rad |
LD | lethal dose that kills 50% of population dose is 500 remm in humans |
REM | (rad equivalent for man) measures biological effect on radiation (tissue damage) |
Background Radiation | expose to low levels of radiation everyday |
Average dose/year of Background Radiation | .27 rem |
Intensity vs Distance | follows the inverse square law instensity of radiatoin is inversely proportional to the square of the distance from the sum |
Intensity vs Distance equation | look at notes |
Radioisotopes are used for | diagnosis & treatment |
Radioisotopes | 1) short 1/2 lives 2) product of decay must b e stable & quickly eliminated 3) 1/2 lives must be long enough to be administered |
PET | Positron Emission Tomography scans used to detect tumors, cancer, coronary-artery disease |
Only device that uses radioisotopes | PET |
These devices use radiation | CT Scan MRI X-Rays |
CT Scan | Computed Tomography used to detect tumors, hemorrhages measures degree of adsorption of x-rays |
MRI | Magnetic Resonance Imaging uses low energy radio waves to get pictures of soft tissue |
X-Rays | use electromagnetic radiation different tissue densities interact different |
Fission | used in nuclear power plants heat |
Steps of Fission | 1) begins when a Neutron collides w/ nucleus of uranium atom 2) resulting nucleus is unstable & splits into 2 smaller nuclei 3) release other Neutrons & gamma radiation 4) chain reaction occurs 5) waste products have a long 1/2 life |
Fission equation | look at notes |
Fusion | 2 nuclei combine to from a larger nucleus |
facts about Fusion | 1) tremendous amount of energy released 2) less waste than fission 3) not practical - high temps (100,000,000 degrees Celsius) 4) "cold fusion" |
Nuclear Reactions | processes that involve changes in the nucleus of atoms |
Radioactive isotopes are used to | diagnose disease visualize organs treat tumors |
Atomic Number | the # of protons in the nucleus |
Mass Number | protons + neutrons in nucleus |
Isotopes | atoms of the same element having a different # of neutrons |
Isotopes have | same atomic number different mass number |
Radioactive isotope is also called? What is it? | Radioisotope Unstable and spontaneously emits energy to form a more stable nucleus |
Artificial Isotope | produce in the lab |
Beta particles has no what? | mass Mass # is 0 |
symbol for gamma ray | look at notes |
In a nuclear equation the _____ _______ & the ______ ______ of the nuclei must be ___________. | mass numbers atomic numbers balanced |
in nuclear equations what is made? | a different element |
What is used in carbon dating? Dating archaeological specimens | carbon-14 |
In a beta emission, _________________ of the original nucleus decays to a ____________________ & _____________. | one neuron beta particle proton |
In a beta emission, the new nucleus has _______________ & __________________ than the original Nucleus. | one more proton one fewer neutron |
In alpha emission, the nucleus has ______________ creating a _________________ | one fewer proton different element |
What is used in medicine and why? | Beta radiation b/c it is composed of high energy, rapidly moving electrons that penetrate tissue in small regions killing tumor cells that are in close contact |
Iodine-131 is used for what | is incorporated into thyroid hormone thyroxine used to treat hyperthyroidism, which results from an overactive thyroid, it destroys thyroid cells by radioactive isotopes, which decreases the activity of the thyroid bringing the disease under control |
Aplha Emission | decay of a nucleus by emitting an alpha particle |
Beta Emission | decay of a nucleus by emitting a beta particle |
Positron Emission | the decay of a nucleus by emitting a positron |
What is the result of a positron emission? | the new nucleus has one less proton and one more neutron than the original nucleus |
The m in technetium-99m stands for what? | metastable meant to indicate that the isotope decays to a more stable form of the same isotope |
What radioisotope is used for the PET scans? | flourine-18 |
Gamma Emission | the decay of a nucleus by emitting gamma ray radiation |
what is technetium-99m used for? | radioisotope used for medical imaging emits high-energy gamma rays decays in short period of time used to image the brain, thyroid, lungs, liver, skeleton, and many other organs |
Gamma emission sometimes? | occurs alone |
Gamma emissions commonly? | accompanies alpha & beta emissions |
Cobalt-60 is used for | eternal radiation treatment for cancer |
Gamma radiation from the decay of cobalt-60 is used for? | a variety of tumors, especially those that cannot be surgically removed |
radioisotopes with a short 1/2 life are used in in diagnosis and imaging because? | they do not linger in the body |
the 1/2 life of a radioactive isotope is a property..... | of a given isotope and is independent of the amount of sample, temperature, and pressure |
Radiocarbon Dating | determine the age of carbon-containing material derived from plants or animals |
Radiocarbon dating is based off of what? | based on the face that the ratio of radioactive carbon-14 to stable carbon-12 is a constant value in a living organism that is constantly taking in CO2, and other carbon-containing nutrients from its surroundings. |
how is the age of an object determined in radiocarbon dating? (part one) | once the organism dies, C-14 decays w/o being replenished, thus decreasing its concentration, while C-12 remains the same. |
how is the age of an object determined in radiocarbon dating? (part two) | By comparing the ratio of C-14 to C-12 in an artifact to the ratio of C-14 to C-12 in organisms today, the age of the artifact can be determined. |
what can radiocarbon dating be applied to? | anything substance that contains carbon |
Geiger Counter | - a small portable device used for measuring radioactivity - consists of a tube filled w/ argon gas that is ionized when it come into contact w/ nuclear radiation - generates an electric current that produces a clicking sound or registers on a meter |
Geiger Counter used for? | to locate a radiation source or a site that has become contaminated by radioactivity |
disintegrations per second | the amount of radioactivity in a sample is measured by the # of nuclei that decay per unit of time |
Becquerel | An SI unit used to measure radioactivity, abbreviated as Bq 1Bq = 1 disintegration/s |
since each nuclear decay corresponds to one becquerel, | 1 Ci = 3.7 x 10 to the tenth Bq |
Often a dose of radiation is measure in...... | the number of millicuries that must be administered |
Radioactivity can not be? | seen, smelled, tasted, heard, or felt yet it can have powerful effects |
Gamma Rays are used in what industry | the food industry |
what are gamma rays used in the food industry | to decrease the incience of harmful bacterie in foods, certain fruits & veggies are irradiated with gamma rays that kill any bacteria contained in them, |
Foods do not come into contact with what? and is not what? | radioisotopes radioactive after irradiation |
Gamma rays merely_________food; destroying any ________; which can cause the food to______ | penetrates live organisms have a considerably longer shelf life |
REM definition | n) is the amount of radiation that also factors in the energy and potential to damage tissue, using rem as a measure of radiation, 1 rem of any type of radiation produces the same amount of tissue damage |
a does of 25-1oo rem can cause | temporary decrease in white blood cell count |
symptoms of radiation sickness | nausea vomiting fatigue prolonged decrease of white blood cell count |
what is the dose that can cause radiation sickness | a dose of more than 100 rem |
a dose of 600 rem of radiation is? | fatal for an entire population |
the isotope is ______ or _______ and the radiation it emits can be used to produce a scan | ingested injected |
HIDA | hepatobiliary imindoacetic acid scan uses techmetium-99m to evaluate the functioning of the gall bladder and the bile ducts |
Thallium-201 is used to | used in stress tests to diagnose coronary artery disease |
Nuclear fission | splitting apart of a heavy nucleus into lighter nuclei and neutrons |
Nuclear fusion | joining together of two light nuclei to from a larger nucleus takes place in the sun |
chain reaction | |
critical mass | |
in a nuclear power plant utilizes the tremendous amount of energy to produced by fission to...... | heat water to steam, which powers generator to produce electricity. |
most of electricity generated in Europe comes from | nuclear power |
2 problems that come with nuclear power | radiation leaks disposal of nuclear waste |
Nuclear Power Plants are designed and monitored to..... | contain the radioactive materials within the nuclear reactor |
the nuclear reactor core is a | containment facility if a nuclear leak should occur Chernobyl, Russia did not have this |
products of nuclear fission have | long 1/2 lives often last for hundreds or thousands of years must be stored in secure facility that doesn't pose hazard to surroundings burying is consider best option, yet is still not resolved |