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Mass times avogadro's numbers = molar mass ?

  1. Feb 9, 2009 #1
    mass times avogadro's numbers = molar mass ??

    Quick questions while I was reading my textbook:

    apparently my textbook shows that

    mass x avogadro's numbers = molar mass of the substance???

    this makes no sense to me.

    Isn't mole/mass = molar mass????

    Can someone please help?
  2. jcsd
  3. Feb 10, 2009 #2
    Re: mass times avogadro's numbers = molar mass ??

    Mass is an extensive property of matter (extensive means that the property changes depending on how much matter there is).

    Avogadro's Number is the number of molecules in one mole of matter.

    The molar mass is the mass of one mole of matter. For example, consider two molecules A and B (assume they are not the same molecule). Since the molecules have different masses, if we take Avogadro's Number of A and Avogadro's Number of B (the same number of molecules), the total mass of each sample will be different. This total mass for one mole of A is the molar mass of A.

    So you get an equation:

    Mass of molecule * Avogadro's Number = Molar Mass
  4. Feb 11, 2012 #3
    Re: mass times avogadro's numbers = molar mass ??

    Thank you for making it Clear.

    Now It makes sense to me :)
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