I heard that any given time there are only 20 atoms in existence.\nIs this for real?
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Francium is radioactive. Its most stable isotope has a half life of only 20 minutes or so. \nThis means that the only Francium present in the earth crust are those atoms that originated from other atoms having decayed. Francium has been detected in Uranium ores but the total quantity present at any time does not exceed 20 grams or so.
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Thats hard... What is it all? Is "it all" before today? Well, then you have yesterday... Year, last year... Its kinda vauge... Before Creation? Maybe nothing, Maybe the first Atom, (atomic particle thingy)  Maybe negative-space? Who knows? Not me... Do you?
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Indeed, the number of neutrons in Bromine (79.904 amu) is 45.\n\nThe AMU is given as a decimal because it is the average AMU of a mole of Bromine atoms(a really lot of atoms). On the Periodic Table round the given AMU and you will have the most commonly occurring isotope (atoms of the same elements with different numbers of neutrons).\n\nGet an "A".
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there are stars out there that haven't been discovered yet.  There is a finite amount of atoms in a grain of sand.  The period at the end of this sentence can hold about 250,000 atoms across.  So a grain of sand would have less atoms than there are stars in the universe.
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It has a 2 microsecond half life, so it is not abundant anywhere. You can hardly keep it in a jar.\n\nIt is made at supercolliders, such as CERN.
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"be a finite amount of matter, but be infinitely small.. which would not exist..."\n\nThat's actually exactly what they are saying...\n\nAs to time warping...  The mistake there is believe that Time is a dimension of it's own rather than the phenomenia caused by change in spacial dimensions and human observations being linear...
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No; very few isotopes have been given individual names (there are far too many of them). The only ones I can think of are deuterium (hydrogen-2) and tritium (hydrogen-3).
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Yes an atom is the same as an element.  A single atom is the smallest particle of an element.  There are 118 different elements in the periodic table. For example, a Hydrogen atom is one proton and one electron.  The next element in the periodic table is Helium, it has one proton, one neutron and one electron.  Each of these atom examples represent their own element.  So you see a single atom does represent it's own particular element, as discussed in the Hydrogen and Helium examples.
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CHEMISTRY I: ATOMS AND MOLECULES\nTable of Contents\nAtoms | Electrons and energy | Chemical Bonding | Chemical reactions and molecules\n\nLearning Objectives | Terms | Review Questions | Links\nAtoms | Back to Top\n\nMost of the Universe consists of matter and energy. Energy is the capacity to do work. Matter has mass and occupies space. All matter is composed of basic elements that cannot be broken down to substances with different chemical or physical properties. Elements are substances consisting of one type of atom, for example Carbon atoms make up diamond, and also graphite. Pure (24K) gold is composed of only one type of atom, gold atoms. Atoms are the smallest particle into which an element can be divided. The ancient Greek philosophers developed the concept of the atom, although they considered it the fundamental particle that could not be broken down. Since the work of Enrico Fermi and his colleagues, we now know that the atom is divisible, often releasing tremendous energies as in nuclear explosions or (in a controlled fashion in) thermonuclear power plants.\n\nSubatomic particles were discovered during the 1800s. For our purposes we will concentrate only on three of them. The proton is located in the center (or nucleus) of an atom, each atom has at least one proton. Protons have a charge of +1, and a mass of approximately 1 atomic mass unit (amu). Elements differ from each other in the number of protons they have, e.g. Hydrogen has 1 proton; Helium has 2.\n\nThe neutron also is located in the atomic nucleus (except in Hydrogen). The neutron has no charge, and a mass of slightly over 1 amu. Some scientists propose the neutron is made up of a proton and electron-like particle.\n\nThe electron is a very small particle located outside the nucleus. Because they move at speeds near the speed of light the precise location of electrons is hard to pin down. Electrons occupy orbitals, or areas where they have a high statistical probability of occurring. The charge on an electron is -1. Its mass is negligible (approximately 1800 electrons are needed to equal the mass of one proton).\n\nThe atomic number is the number of protons an atom has. It is characteristic and unique for each element. The atomic mass (also referred to as the atomic weight) is the number of protons and neutrons in an atom. Atoms of an element that have differing numbers of neutrons (but a constant atomic number) are termed isotopes. Isotopes can be used to determine the diet of ancient peoples by determining proportions of isotopes in mummified or fossilized human tissues. Biochemical pathways can be deciphered by using isotopic tracers. The age of fossils and artifacts can be determined by using radioactive isotopes, either directly on the fossil (if it is young enough) or on the rocks that surround the fossil 9for older fossils like dinosaurs). Isotopes are also the source of radiation used in medical diagnostic and treatment procedures.\n\nNote that each of these isotopes of hydrogen has only one proton. Isotopes differ from each other in the number of neutrons, not in the number of protons. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission.\n\nSome isotopes are radioisotopes, which spontaneously decay, releasing radioactivity. Other isotopes are stable. Examples of radioisotopes are Carbon-14 (symbol 14C), and deuterium (also known as Hydrogen-2; 2H). Stable isotopes are 12C and 1H.\n\nCarbon has three isotopes, of which carbon-12 and carbon-14 are the most well known. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission.\n\nThe Periodic Table of the Elements provides a great deal of information about various elements. An on-line Periodic Table is available by clicking here, or if that is busy try a mirror site.\n\nThe Periodi
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it is possible that an atom can support life like the earth does,  but if it does, then it would be way different and ofcource smaller. the things that make up the earth perfect to support life may be different in an electron. but it is something to think about. interesting question
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The MOST recently discovered element was atomic number 118.  It is being temporarily called 'ununoctium'.  As to WHEN it was discovered... that's a little more complicated.\n\nA team of element-makers at Lawrence Berkeley lab claimed to have made it in 1999, but when nobody could reproduce the find with the lab's methods (even the original lab), their finding was discredited.\n\nIn Spring of 2002 (it took four months) the Joint Institude of Nuclear Research in Dubna claimed to have produced an atom of ununoctium.  This was confirmed by Dubna and the Berkeley lab when each of them produced another atom in 2005.\n\nThe average lifespan of these three atoms was just under a thousandth of a second.  So don't expect any accumulation of the stuff!
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Zero of zero is undefined because of the definition of division and some basic field axioms.  It's not zero and it's not infinity, it's UNDEFINED.  I can prove it.\n\nThe multiplicative inverse of n is defined as the number 1/n such that n*(1/n)=1.  It's a property of zero that anything times zero is zero.  Therefore for any 1/n, 0*(1/n)=0, and since zero cannot equal one, zero has no multiplicative inverse.\n\nDivision by n is defined as multiplication by the multiplicative inverse of n.  Since zero has no multiplicative inverse, you cannot divide by zero.\n\nAll you people who said that anything divide by zero is infinity are just flat out wrong.  If n is not equal to zero, the limit as x approaches zero for the positive side of n/x is infinity, but that does not mean that n/0 is infinity.  Also, note that if you come at it from the negative side the limit is negative infinity.  n/0 is undefined because zero has no mutiplicative inverse so the expression 1/0 is mathematically meaningless  Also, the limit of 0/x as x approaches zero would be zero, not infinity.\n\nWhoever it was who did the calculator thing, calculators are a far cry from a mathemtical proof.   There are plenty of arithmetic problems that make perfect sense but can't be done on a calculator.  In fact, there are infinetly many of them.  And there are some properties of multiplication and addition that can be proven mathematically but are not true on a calculator.  But you and the first poster get major props for being the only people to answer this question and demonstrate anything resembing an basic understand of elementary arithmetic.\n\n______\nH2++ cannot exist because it would have to have a covalent bond but would have no electrons.  Two hydrogen nuclei can't form a diatomic molecule.  O-- is not going to exist in water because the hyrogen atom would have to dissociate from the water molecule one at a time, and OH- is more stable than O-- and H+.  It could in theory exist as 2H+ and O--, but OH- is a much happier molecule than O--.\n\nNothing can go faster than the speed of light because as an object approaches the speed of light it's mass becomes infinite, and so the force required to cause it to accelerator more becomes infinite.  You can't apply infinite force to something.  Normally I'd do out the math to show that, but it's 3:30 in the morning so I doubt I can make it coherent.\n\nTensor calculus is too complicated to explain at 3:30 in the morning.  You can read about it here: http://en.wikipedia.org/wiki/Tensor_calculus
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Yikes, I'll try, but it's tricky even for me!  And I've read a lot about it because it fascinates me!\n\nOK, the idea is that you have a cat in a box.  The cat is not visible to you, the experimenter.  In this box is a small amount of radioactive material and a geiger counter.  If one atom decays even the tiniest amount and the geiger counter catches this, a tiny flask of poison is broken and the cat is killed.  The "weird" part (hah) comes in here.  Whether or not the atom decays is strictly a probability issue.  However, using quantum mechanics, the cat would neither be alive nor dead until someone opened up the box to give it a "label" - to observe it and quantify it as alive or dead.  It would exist in a state of "alive/dead"ness, sort of.  \n\nSchrodinger used this as a way of pointing out that sometimes quantum mechanics just doesn't work for a given situation.
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Probably not.  There are several problems\n\n1) because of the Heizenberg(sp?) uncertainty principle to learn of the exact direction of an atom one would change it's original direction.\n\n2) even if we could know a priori all that information it would require a simulation machine the size of the universe to calculate everything exactly.\n\n3)  I think there are still events of randomness at the atomic level that cannot be predicted.
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Good question - it depends on which theory you want to use. Currently, it is estimated that there are 5 hydrogen atoms per cubic metre. But this does not necessarily mean that there is "nothing" between these atoms.\n\nAccording to quantum physics, even the space that we most often referred to a a vacuum, may be composed of various exotic unobservable (for now) components.\n\nIn quantum physics a vacuum is not the same thing as "nothing." One theory supposes that all space is filled with the Higgs Ocean composed of an undetected Higgs field.\n\nThe current idea in quantum physics is that the only place where there is "nothing" is between the strings making up all matter and energy. The concept of "nothingness" is a complex and extensive subject and very difficult for us to visualize.\n\nOf course there is much more to these concepts than a few words in a brief paragraph can relay.\n\nGood Luck
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Before you start calling people stupid that correctly answer a question you ask, you need to check your own sources first.\nUntil the 1900's the atom was considered the smallest bit of matter, that it was like a very tiny ball that couldn't be broken up into smaller bits.\nBut the early 1900s saw the birth of nuclear physics and quantum theory, and while the atom is the smallest "collection" of matter that makes up all the bigger things we see, it is not the smallest particle in the universe.  The atom itself is like a family of particles (electrons, neutrons, and protons).  The proportions of how many of each particle is what makes each element different.\nIn very simple terms (physics majors out there, forgive me for being simplistic), a hydrogen atom consists of one proton and one electron, while the helium atom consists of 2 neutrons + 2 protons + 4 electrons.  Its the different numbers of those "sub-atomic particles" that govern what element the atom is and what its properties are.\n\nSomething to consider for yourself - you need to read some more and learn that is a lot out there that you don't know.\nScientific American, Discover, and National Geographic are excellent magazines to help get you into the 20th century.  And with a little time, you'll join the rest of us in the 21st century.\nGood luck.
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It's impossible to be all-knowing. The more you know, the more complex your brain would need to be. And that increases the amount of information there is to know. Can a computer be aware of every atom it is composed of? And to know the future is even more impossible.