standards describe radioactivity and nuclear decay

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Describe radioactivity and nuclear decaypower point notes movie


I. Background InfoII. Types of radiation III. Other info

What do you already know about radioactivity?

My part in producing the atomic bomb consisted in a single act: I signed a letter to President Roosevelt, pressing the need for experiments on a larger scalein order to explore the possibilities for the production of an atomic bomb.

I was fully aware of the terrible danger to mankind

in case these attempts succeeded.

But the likelihood that the Germans were working on the same problemwith a chance of succeeding, forced me to this step.

I could do nothing elsealthough I have always been a convinced pacifist.

To my mind, to kill in war is not a whit betterthan to commit ordinary murder.Albert Einstein, 1952

RadioactivityI. Background informationradioactivity process of nuclear decaynuclear decay-the breaking apart of the nucleus, it does not split!All elements with atomic number of 83 and higher are radioactive..

INTERACTIVE PERIODIC TABLE:As a nucleus breaks down, energy is given off.What is this energy called?RADIATION

radiation - energy given off during nuclear decay II. Types of radiation3 types of radiationAlpha particles2. Beta particles

3. Gamma raysAlpha particles - can go only a few cm, can be stopped by paper, skinAlpha particles come from:

Earths crust mining wasteTobacco leaves give off small amounts of alpha particles.


Interferes with normal cell processesWe have to eat it, breathe it or have an open wound for it to hurt us.The greatest danger for us comes from breathing radon. Radon, is a heavy gas and tends to collect in low-lying areas such as basements. FYISome natural springs, such as those at Hot Springs, Arkansas, contain radon, and were once considered healthful.


can be used to treat cancer by putting tiny amounts of it into a tumor. Beta particles - can go several feetcan be stopped by foil, clothesBeta particles come from:

Earths crust Some old industrial instruments

People who have been given radioactive medical treatments

Nuclear accidents

FYIAt one time, strontium-90 was the major man-made beta emitter in the environment. Fallout from atmospheric nuclear testing from the 1950's to the early 1970's spread strontium-90 worldwide. However, most of the strontium-90 from these tests has now decayed away.Testing also released large amounts of cesium-137 into the environment. Although, cesium-137 emits beta radiation, its gamma radiation is of greater concern. Some cesium-137 from fallout remains in the environment, but most of it has decayed as well.DANGERS:

Interferes with normal cell processesCauses burnsMost damage is done if we eat it, breathe it or have an open wound.BENEFITS:

Medical treatments ex)radioactive iodineGamma rays - Can go thousands of meters

go the speed of lightcan be stopped by thick dense objects such as lead or concrete

No particles are involved, they are energyGamma rays come from:

SpaceNuclear accidents


Radiation sickness - large exposures in short time periods, the most severe damage of all radiation: burns, blindness, cancer,death


treat cancer sterilize medical equipment in hospitals clean certain foods and spices

In the United States, a persons average exposure to radiation is about 360 millirem per year. Roughly 300 millirem come from natural sources of radiation, and 60 millirem come from man-made sources, primarily medical procedures.

More info on exposure:

half life = time it takes for half of the nucleus to break apartSodium 24 - 15 hrsIron 59 45 daysCobalt 60 5 yrsUranium 235710 mill yrs.III. Other InfoCarbon -14 dating


Baby wooly mammoth


The results of radiocarbon measurements at Arizona, Oxford and Zurich yield a calibrated calendar age range with at least 95% confidence for the linen of the Shroud of Turin of AD 1260 - 1390 (rounded down/up to nearest 10 yr). These results therefore provide conclusive evidence that the linen of the Shroud of Turin is mediaeval.

GALILEOS FINGERCarbon on the periodic table is Carbon 12. It is stable it does not decay.Carbon 14 is an isotope of Carbon 12.

Carbon 14 is not stable. It will decay. It takes 5,700 years for half of the nuclei in Carbon 14 to break down.

Carbon 14 has a half life of 5,700 years.

Plants use CO2 for photosynthesis so they have Carbon 14 in them.Animals eat plants so animals have Carbon 14 in them.Living things also have Carbon -12 in them.The amount of Carbon-14 and Carbon 12 in a living thing remains constant.All living things have the same percentage of Carbon-14 and Carbon -12.When a living thing dies, the amount of Carbon -12 stays the same becauseCarbon -12 does not decay (it is not radioactive).

Carbon 14 does break down. We can measure the amount of Carbon -1 2 and Carbon -1 4 in the fossil. Scientists burn a small piece of the object. A radiation counter measures the amount of Carbon -14 and Carbon - 12. By comparing the amounts, we know how much Carbon -14 should be there.

A formula is used to figure out the age.Carbon - 1 4 dating is only good for fossils up to 60,000 years old. Why?5,700 5,700 5,700

and on and on


Carbon 14 DatingCarbon -1 4 is radioactive

small piece of the artifact must be burned to test ithalf life is 5,700 yearsused to age artifacts up to 60,000 years oldWhy is Carbon-14 only good for dating artifacts up to 60,000 years old? Since the half-life of Carbon-14 is 5,700 years, all of it will have decayed into Carbon-12 in 60,000 years.nuclear decay nucleus doesnt split, it just breaks down

Benefits of nuclear energyReduces dependence on oil for electricityNo pollutants released into atmosphere(burning of coal pollutes atmosphere)Drawbacks of nuclear energystorage of waste it can last thousands of years(Waste from burning coal can last forever) MT.Katie CourickShutting it down

meltdown chain reaction cannot be stopped, the core overheats releasing radiation

In the night of April 26, 1986

the explosion of the nuclear reactor in Chernobyl, the greatest industrial disaster in the history of humankind,

released one hundred times more radiation

than the atom bombs dropped over Hiroshima and Nagasaki.More than 40 different radionuclides escaped,

notably in the first ten days following the accident.

Radioactive iodine, with a half life of 8 days, posed the greatest risk in the first few weeks. Radioactive caesium, with a half life of 30 years, is still the most widely dispersed isotope. Between 125 000 and 146 000 km2 are contaminated with caesium.

There is long term contamination with strontium which has a half life of 29 years,

and plutonium with a half -life of24,000 years.

Chernobyl disaster incident PART 1

Vacation in chernobyl (no pw),32068,1449613919_1728561,00.html

Chernobyl mystery

It happened in


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