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Atoms vs. Elements

  1. Jan 18, 2005 #1
    Guess I'll be flippin' burgers for the rest of my life guys... I can't figure out the difference between elements and atoms! I've searched the internet and wrote down their definitions and I e-mailed my prof. Here is how he explained it:

    > Atoms are the fundamental building blocks of matter and differ from
    > each other in the number of protons (different elments) and numbers of
    > neutrons (isotopes of an element). The term atoms is used to discuss
    > how many atoms of an element we have, or to talk about particles of
    > matter in general without discussing the identity of the atoms
    > (elements). The term element is used to differentiate between atoms,
    > ie, the compound contains 3 different elements.

    Maybe 'element' is just a general term for all atoms with the same # of protons. I'm looking for a GOOD definition here.
    Why could we not just call every symbol on the periodic table an atom with a different atomic #?
  2. jcsd
  3. Jan 18, 2005 #2
    Elements vs. atoms

    You are basically right. The word "element" was introduced, and even the periodic table constructed, before atomic theory was known. Now that we know that the reason that the substances we call elements (gold, helium, uranium), are special is that they are composed of identical atoms (unlike, componds, such as salt or carbon-dioxiode, which are composed of more than one type of atom), we could consider changing our terminology -- "The Periodic Table of the Kinds of Atoms" is a perfectly fine suggestion.

  4. Jan 18, 2005 #3


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    An element is a name for a specific substance. Gold is an element, as is aluminum and iron and so on. An atom is the smallest possible piece of that substance that retains all its properties. A single atom of gold has 79 protons, (roughly) 117 neutrons, and 79 electrons. This single atom exhibits all of the chemical properties of the substance we call 'gold.' Any further subdivision of a gold atom -- for example, breaking it up into protons and neutrons -- will result in pieces which do not exhibit the properties of gold.

    We could, indeed, just refer to 'gold' as 'all atoms with 79 protons in them,' but 'gold' is a little easier to say.

    - Warren
  5. Jan 19, 2005 #4
    Thank you! I will just remember the "element" defintion for the test;

    "We could, indeed, just refer to 'gold' as 'all atoms with 79 protons in them,' but 'gold' is a little easier to say."

    Yes, and the word element never HAS to be mentioned. We could just say that all gold atoms have 79 protons and be done with it.

    *crosses out "Periodic Table of Elements" title and replaces with "The Periodic Table of the Kinds of Atoms"*
  6. Feb 14, 2005 #5
    Why do we use Dalton's laws then?...
  7. Feb 14, 2005 #6


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    Dalton's Law talks about partial pressures and has nothing to do with the above discussion.

    If you have a specific question, ask it. If it is not related to the flow of this thread start a new one.
  8. Feb 14, 2005 #7


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    I'd bet he was referring not to Dalton's law, but to the other laws related to Dalton atomic theory, such as the Law of Constant Composition (by Proust?) and specially the Law of Simple Multiple Proportions (by Dalton himself). Some dictionaries in the net refer to this Law also as Dalton's Law, but you could prefer "Dalton third postulate". Note also that the previous poster referred to "Dalton's laws", in plural, so it could be safely inferred he was pointing to the postulates.

    In any case, it is obviously related to the thread.
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