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Homework Help: 2 chemistry questions

  1. Oct 3, 2006 #1
    1) mass (grams) of 111 gold atoms

    would i simply multiply the atomic weight of Au by 111?

    2) Why is the atomic mass of S = 32.066?

    is it because this is how much the neutrons and protons weigh?
  2. jcsd
  3. Oct 4, 2006 #2
    1.) No. The atomic weight of gold as listed is the weight in grams of on mole of gold atoms. You must find out how many moles 111 atoms is then use that number

    2.) Sort of. Yes the atomic mass is the mass of all the stuff in the atom ie protons neutrons and electrons (though the mass of electrons is negligible normally). However the reason that its not a whole number is due to it being an average of different isotopic masses.
  4. Oct 4, 2006 #3
    Avagadro's number FTW! FunkyDawrf gave you a perfect definition of the atomic mass. Also the atomic mass is actually the average atomic mass. Just a good thing to keep in mind
    Last edited: Oct 4, 2006
  5. Oct 9, 2006 #4
    i said in my original...
    I did keep it in mind :)
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