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Homework Help: Atoms and molecules

  1. Jan 27, 2006 #1


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    say for example, a question states that you have 18 g of H20 which is obviously one mole.

    now if they asked how many molecules of water you had, you would just multiply the one mole by avagadros number (6.022 * 10^23) to get that answer.

    if they asked how many atoms of water, would it be the same?

    now what if they asked how many atoms of hydrogen would be created? would you then take the previous answer and multiply by 2?

    is that correct?
  2. jcsd
  3. Jan 27, 2006 #2
    there's no such thing as an atom of water, but if they asked you how many atoms are in a mole of water, you would take the number of molecules of water and multiply it by 3 to get the atoms.

    if they wanted the atoms of hydrogen, then your answer would be correct.
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