Does the Periodic Table Evolve ?

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river

Not elements created by us .

Does Hydrogen , Oxygen , any element evolve , change so much that the definition of the element then changes .
 
river said:
Not elements created by us . Does Hydrogen , Oxygen , any element evolve , change so much that the definition of the element then changes .
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No. Some minor changes (like average atomic weight) might occur as we change our estimates of isotope ratios, and new elements are added as they are discovered. But oxygen isn't going to change atomic number tomorrow.
 
How long is the life span of an atom?
Atoms are forever! But let me explain. Atoms are made of a central core containing a collection of protons and neutrons. Almost all of the mass (the proper word for "weight") of the atom is contained in the nucleus. Surrounding the nucleus is a cloud of electrons whose number equals that of the number of protons. (This is necessary to keep the electrical charge of the atom zero.) The number of protons determines the identity of the atom. So, hydrogen has 1 proton, oxygen has 8 protons, iron has 26 protons, and so on. The number of neutrons is usually fixed for a particular atom (for example, the most common form of carbon has 6 neutrons), but this does not have to be so.
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Sometimes, when an atom doesn't have the 'right' number of neutrons, it becomes unstable and shoots out sub-atomic particles, a common one being the electron. What is happening is that one of the neutrons in this neutron-enhanced version of the atom, is changing into a proton plus an electron (plus a zero mass particle called the anti-neutrino, but we can chat about that some other time). This electron is spat out of the nucleus. This is an example of a "radioactive" atom. Essentially they are special versions of a particular atom that are trying to change to a stable type of atom, that is, one that will NOT change with time.
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https://education.jlab.org/qa/radelement_03.html#
 
But this is an interesting question.

Carbon-14 dating
Alternative Title: radiocarbon dating
Carbon-14 dating, also called radiocarbon dating, method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon-14). Carbon-14 is continually formed in nature by the interaction of neutrons with nitrogen-14 in the Earth’s atmosphere; the neutrons required for this reaction are produced by cosmic rays interacting with the atmosphere.
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Radiocarbon present in molecules of atmospheric carbon dioxide enters the biological carbon cycle: it is absorbed from the air by green plants and then passed on to animals through the food chain. Radiocarbon decays slowly in a living organism, and the amount lost is continually replenished as long as the organism takes in air or food.
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Once the organism dies, however, it ceases to absorb carbon-14, so that the amount of the radiocarbon in its tissues steadily decreases. Carbon-14 has a half-life of 5,730 ± 40 years—i.e., half the amount of the radioisotope present at any given time will undergo spontaneous disintegration during the succeeding 5,730 years. Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon.
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The carbon-14 method was developed by the American physicist Willard F. Libby about 1946. It has proved to be a versatile technique of dating fossils and archaeological specimens from 500 to 50,000 years old. The method is widely used by Pleistocene geologists, anthropologists, archaeologists, and investigators in related fields.
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https://www.britannica.com/science/carbon-14-dating

Now there is a great mystery!
Now, here's a question for all you hotshots out there. Carbon-14 is a popular atom to look for when figuring out the age of old organic matter, for example, some bits of wood found in an old Egyptian tomb. Now, knowing that the half-life is only about 6,000 years, and the age of the Earth is about 4 billion (4*109) years, it doesn't take an Einstein to see that ALL of the carbon-14 should have converted to nitrogen long ago. Something must be PRODUCING the stuff even as we sit here staring at a computer monitor. Any ideas?

Author: Carl Zorn, Detector Scientist (Other answers by Carl Zorn)
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https://education.jlab.org/qa/radelement_03.html#
 
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Write4U said:
But this is an interesting question.

Carbon-14 dating
Alternative Title: radiocarbon dating
https://www.britannica.com/science/carbon-14-dating

Now there is a great mystery!

https://education.jlab.org/qa/radelement_03.html#
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As all ready pointed out. that was answered in the first paragraph. C14 is formed in the atmosphere by this process. The atmospheric C14 finds its way into living organisms ( plants take in CO2, animals eat plants...)
Once a plant or animal dies, it quits taking in new carbon. New C14 is no longer added, and the existing C14 decays.
As a result, carbon dating is only useful for dating things that contain materials that was organic and once part of a living organism, and it tells us when it was last a part of something living. Human remains is one example. Pottery, for instance, can be dated by animal fat residues left behind.
Radiocarbon dating becomes unreliable for anything older than 30,000 yrs. For older object, other types of dating is used (Uranium-Thorium dating can work up to 500,000 yrs and Uranium-Lead dating can date rocks up to 4.5 billion years old)
 
How could we take the most stable elements we can think of and make anything unstable? Just a question. Not really.
 
river said:
Then the Periodic Table is Stable , as it is .
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There was a TV show where the characters would travel through "wormholes" to "alternate universes". In one of those alternate universes, they noticed that there were no aircraft and the proposed explanation was that "maybe they don't have aluminum in their periodic table."

If you understand what a periodic table is, maybe you can understand where their thinking went wrong.
 
Beaconator said:
I guess your right, but I was referring to taking already stable elements and mixing them to make a stable product.
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When you say "mixing", do you mean reacting them chemically, to produce a compound from them, or something else?
 
Beaconator said:
To produce a compound from them
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Well you can react two stable elements to make a stable compound. How about reacting Fe and S to form FeS, for example?

(And don't forget "stability" has both a thermodynamic and a kinetic aspect ;).)
 
exchemist said:
Well you can react two stable elements to make a stable compound. How about reacting Fe and S to form FeS, for example?

(And don't forget "stability" has both a thermodynamic and a kinetic aspect ;).)
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What is the largest compound containing the most different elements?
 
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