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Find the mass

  1. Jan 6, 2005 #1
    What is the mass (in grams) of 6.022 x 10^6 atoms Carbon 12? I am given the equation 1 amu=1.6606 x 10^-24 g, but I'm not sure if I should be using this in my conversion factor or not. Can anyone tell me how to set this up? I have a few ideas but unfortunately I don't have any way to check my answers to see if they're correct. Thanks in advance
  2. jcsd
  3. Jan 6, 2005 #2


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    * 1 amu (apud 'atomic mass unit') is,by definition,the 12-th part of the mass of an atom of C-12,or numerically,[itex] \sim 1.66\cdot 10^{-27} Kg [/itex]
    ** So from "*" u can find the mass of a C-12 atom.
    ***Knowing the mass of an atom,it won't be too hard to find the mass of [itex] 6.022 \cdot 10^{6} [/itex] atoms.

  4. Jan 7, 2005 #3
    6.022 x 10^23 is avagadro number N,N no: atoms weigh 1 amu.
  5. Jan 7, 2005 #4


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    No poolwin, the mass of [itex]N_{av} [/itex] atoms is the molar mass of the element.

    As Dexter has said already, [itex]1~ amu =\frac {mass~of~a~C-12~atom}{12}[/itex]
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