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Please discribe mole and how it works!

  1. Nov 18, 2012 #1
    I don't know what mole is and I read a lot of answers, is it like a dozen of atom, or is it like a unit, like meter?or is it something else?
  2. jcsd
  3. Nov 18, 2012 #2
    A mole is a unit that quantifies 6.022 x 10^23 of a particular element, molecule, or particle.

    so if you had a mole of dogs, you would have 6.022 x 10^23 dogs, more than enough to cover the surface of the world! A more likely example is if you had a mole of hydrogen atoms; you would then have 6.022 x 10^23 hydrogen atoms.

    So you are correct in the analogy of it being a "dozen" of something, only it happens to represent about 10^22 times more than a dozen.
  4. Nov 18, 2012 #3
    What does that do, say a mole of hydrogen atoms, what is the purpose of the mole? What can a mole of hydrogen atom achieve? And does it have anything to do with atomic number of hydrogen?
  5. Nov 18, 2012 #4


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    It's just a way to count large numbers of atoms. It's sometimes easier to work with 3 moles of helium, than 18x1023 atoms of helium.
  6. Nov 18, 2012 #5
    What about Avogadro number's, is that the same as mole? And my dad said that mole connects the molecular world to our world(the bigger one), is that true, if it is, how is it true?
  7. Nov 18, 2012 #6
    O, and how do you quote ?
  8. Nov 18, 2012 #7


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    It's the constant that is defined as the number of atoms in a Mole of a substance. It has no actual connection between our world and the quantum world, just a mathematical one. It can be used as a scaling factor for certain things. See here for more: http://en.wikipedia.org/wiki/Avogadro_constant

    Click the "Quote" button at the right side of whatever post you want to quote.
    Or click the "Multi Quote" button next to each post you want to quote and then hit "New Reply" at the bottom of the thread.
  9. Nov 18, 2012 #8
    It doesn't do anything, it is just a representation of a scaling factor (you know this factor as Avogadro's constant). The reason we like using the mole in equations as opposed to just one particle is that it is simply easier. Easier for measurements and easier for calculations. Since it's early use, however, many relationships have been based off of this scaling factor including Boltzmann's constant and other various relationships. The number of particles per mole was originally based off of how many atoms were in 1 gram of hydrogen. It has since been redefined as the number of atoms in 12 grams of carbon.

    The mole doesn't depend on atomic number or vice versa. Molecular weight on the other hand is related to the number of grams per mole.

    I hope that helps.
  10. Nov 18, 2012 #9
    Thank you
  11. Nov 18, 2012 #10
    Thank you
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