Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: taupo19 on 24/05/2009 18:41:27
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As I understand it Atoms are forever - Is this correct? Do atoms have an age? Is there anyway of telling how old an atom in my body (say of carbon) is?
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Some atoms decay into other types of atoms, but we usually think of stable atoms as permanent. Any atom can be reduced to electromagnetic energy when enough force is applied.
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No there is absolutely no way that an atom has an age also all atoms of the same type and in the same energy state are absolutely identical and cannot be distinguished from each other.
It is of course possible for radioactive elements to decay by e,mitting particles or photons and excited atoms to change their energy state towards their ground state by emitting photons but these are random processes that have a half life but it is not possible to know if an atom will decay at any particular moment.
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The my question would be that carbon dating is done through measuring the decay of a carbon 14 atom - is this the case? Why is this atom different?
Is it likely in the future that we'll be able to measure the age of an atom or am I completely misunderstanding the issues here.
Thanks for your replies..
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It is only through the decay of a large number of carbon 14 atoms that the age can be determined. Living material because of its continual biological turnover of atoms has a stable balance between the number of carbon 16 atoms and carbon 14 atoms when it dies this balance is no longer maintained and the carbon 14 atoms decay with a half life of around 5000 years after 5000 years the carbon14 decays have slowed down to half the rate of living material. this allows formerly living material to be dated reasonably accurately over about 10,000 years
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There are two odd things about carbon 14 that let us use it as a "clock". Firstly it is radioactive and decays at a constant rate. Secondly it is made in the upper atmosphere as a result of interactions with high speed particles from the sun.
That means that the amount of C14 in the atmosphere is roughly constant over time but onece you stop breathing and eating your remains no longer get "topped up" with C14 so the amount left starts to fall.
Since you know what the initial level was and you can measure how much it has fallen you can work out how long ago something died.
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Very interesting guys and gals - so when a Carbon 14 atom is created through interaction with the Suns particles there is no 'indicator' of when it happened? Crazy questions I know but it's all leading to something I promise - :)
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There's no way to know the age od an individual atom. They are too small to put "sell by" dates on.
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Very interesting guys and gals - so when a Carbon 14 atom is created through interaction with the Suns particles there is no 'indicator' of when it happened? Crazy questions I know but it's all leading to something I promise - :)
No indicator, except that the C14 has a half life of a few thousand years. It then becomes a regular garden-variety C12 or C13 atom.
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Very interesting guys and gals - so when a Carbon 14 atom is created through interaction with the Suns particles there is no 'indicator' of when it happened? Crazy questions I know but it's all leading to something I promise - :)
No indicator, except that the C14 has a half life of a few thousand years. It then becomes a regular garden-variety C12 or C13 atom.
No, it doesn't.
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Oops; you're right. It is nitrogen-14. Sorry about that; I'm glad you're around to keep me honest. [:)]
There are three naturally occurring isotopes of carbon on Earth: 99% of the carbon is carbon-12, 1% is carbon-13, and carbon-14 occurs in trace amounts, e.g. making up as much as 1 part per trillion (0.0000000001%) of the carbon in the atmosphere. The half-life of carbon-14 is 5,730±40 years. It decays into nitrogen-14 through beta decay.[3] The activity of the modern radiocarbon standard[4] is about 14 disintegrations per minute (dpm) per gram carbon.[5]
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Very interesting guys and gals - so when a Carbon 14 atom is created through interaction with the Suns particles there is no 'indicator' of when it happened? Crazy questions I know but it's all leading to something I promise - :)
No indicator, except that the C14 has a half life of a few thousand years. It then becomes a regular garden-variety C12 or C13 atom.
No, it doesn't.
Well that told him!
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Hopefully it told everyone which, after all, is the point of a science site.
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So to sum up, and thanks for all your answers by the way, atoms can be 'created' through interaction - destroyed through the same but have no 'life span' as far as we can tell..Atoms are forever once created - Can this be the case? Is anything forever?
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It has been suggested that Protons have a life of 10^35 years but experiment has failed to prove this.
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It has been suggested that Protons have a life of 10^35 years but experiment has failed to prove this.
And if this is true, atoms will age and eventually cease to exist in their present form. This is an extremely interesting question, and one that deserves a lot more thought.
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Thanks for the above comments - something tells me that everything has a cycle - a beginning and an end and a beginning.
Keep 'em coming!