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What is Radioactivity?
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  • Written By: Michael Anissimov
  • Edited By: Niki Foster
  • Copyright Protected:
    2003-2012
    Conjecture Corporation
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Radioactivity is the process whereby unstable atomic nuclei release energetic subatomic particles. The word radioactivity is also used to refer to the subatomic particles themselves. This phenomenon is observed in the heavy elements, like uranium, and unstable isotopes, like carbon-14.

Radioactivity was first discovered in 1896 by the French scientist Henri Becquerel, after which the SI unit for radiation, the Becquerel, is named. Becquerel discovered that uranium salts were able to blacken a photographic plate placed in the dark, even through a paper barrier. Subsequent experiments distinguished three distinct types of radiation -- alpha particles, beta particles, and gamma rays. These are positively charged, negatively charged, and neutral, respectively. In the United States, human exposure to radioactivity is measured in rads, where one rad represents 0.01 joule of energy absorbed per kilogram of tissue.

Radioactivity is a random process, meaning that it is physically impossible to predict whether or not a given atomic nucleus will decay and emit radiation at any given moment. Rather, radioactivity is quantified using half-life, which is the period of time it takes for half of the given nuclei to decay. Half-life applies to a sample of any size, from a microscopic quantity to all the atoms of that type in the universe. Half-life varies widely, from a couple seconds (Astatine-218) to billions of years (Uranium-238).

In small doses, radioactivity is a useful process that can be harnessed by man. For example, nuclear reactors exploit radioactivity to generate heat. Phosphorescent materials sometimes include small quantities of radioactive atoms. During pharmaceutical testing, drugs are sometimes laced with radioactive atoms so that they can be more easily traced as they move throughout the body.

In large doses, radioactivity is extremely dangerous. In the Ukraine, a nuclear reactor meltdown incident that occurred during the Cold War era continues to have deleterious effects on the local population to this very day. Many weapons have been designed and tested which use radioactivity to kill people in large numbers. As the level of our science and technology progresses, we can only hope that the peaceful applications of radioactivity will be developed more rapidly than applications for warfare.

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anon208723
Post 43
is radioactivity a curse or a boon?
anon163055
Post 41
anon162619: Check out you smoke detector, it uses trace amounts of radioactive isotope called Americium.
anon162619
Post 40
how is radioactivity useful for us in our daily life?
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cag238
Post 39
Radioactivity is a natural phenomenon that results from the the fact that, entropy increases with time, or, everything will eventually fall to pieces. The nucleus of certain atoms split apart because the repulsive force of the protons eventually overcomes the short range nuclear force.

This is more common as you generally go higher up the periodic table (which is why most elements created by man don't last long, too many protons). Yes, to a degree the human body, and all lifeforms, are radioactive. Every day, at least one atom in your body splits apart. But don't worry. You have hundreds of billions of atoms to go (if not more). It will take a very long time for your body to be reduced to sub-atomic particles (emphasis on very long).

anon102598
Post 37
Radioactivity is not a thing. It is the emission of particles and energy by large, unstable atoms that are seeking a more stable structure. Radiation is the "something" that unstable atoms give off as they seek stability. This can be in the form of alpha particles, beta particles or gamma "photons".
anon100821
Post 36
how do radioactive atoms change structure?
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anon83250
Post 34
But how it is useful for us?
anon80657
Post 32
How can radioactivity be useful to us?
anon78035
Post 31
Is it possible for a person to be radioactive?
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anon70942
Post 29
wasn't radioactivity created by marie curie?
anon68878
Post 28
In your opinion, is radioactivity a blessing or a curse?
anon64460
Post 25
how does radioactive material affect humans?
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anon60799
Post 24
can salt help break down radioactive waste or help speed up the breakdown?
anon45252
Post 21
Why do we have it?
anon45250
Post 19
What does radioactivity do?
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priyasharma
Post 17
how is radioactivity formed?
anon43589
Post 16
how do we use radioactivity in our daily life?
anon40109
Post 15
how is radioactivity formed?
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anon38534
Post 14
what are the effects of radiation in our health and environment?
LordTiberius
Post 13
Is radioactivity considered a physical characteristic?
anon29680
Post 12
Can a neon particle or any noble gas become radioactive?
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marbie99
Post 11
How do we use radioactivity in our daily life?
denyat
Post 10
We work with Copper Concentrate on a daily basis, with readings usually above 0.3mSv. Is this safe? Should we be concerned? What effect will this have on us?
anon23633
Post 9
What is the amount of ir radiation emitted by humans? And what s the amount of ir radiation emitted by dead people? What's the rate of decay?
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anon20335
Post 8
What role did Marie Curie play in the discovery of radioactivity?
anon16809
Post 7
Radioactivity has a lot of applications in various fields.Could u please explain its uses in relation with carbon dating?
anon14078
Post 6
Is there a simpler term in meaning of the word Radioactivity. Eg. In a highschool level?
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anon13753
Post 5
what are the medical applications of radioactivity?
anon9891
Post 3
is radioactivity something that can go through anything or is it something that dissolves into things?

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