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Compare and contrast one mole of a compound and Avogadro's number of particles in a compound.  What is the conversion factor between the two?
 Can you please help explain so that a younger student could understand?????????
Thanks!

hi ;)

1 mole of a molecule has avogadro no. of molecules not atoms , this will become clear from the followin eg.

See let us take NH3 this is a molecule so if i say avogadro no. of NH3 it means 6.023 *10^23 MOLECULES OF NH3 not aatoms
for calculating no. of atoms ....... there are 3 H atoms and 1 N atom so total no. of atoms  = 4 * avogadro no.

so if u take CH3COOH there are 8 * avogadro no. atoms but AVOGADRO NO. OF MOLECULES (COMPOUND)  OF CH3COOH

think about this statement..
"compare and contrast 1 dozen donuts and 12 donuts"

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it's the exact same idea...
1 mole is to 6.022x10^23 as 1 dozen is to 12

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think about what "dozen" actually means.  it's a label we give to a "quantity" of something right?  That quantity happens to be "12".  Likewise "pair" is the label we give the quantity "2".

1 dozen donuts = 12 donuts
1 pair of shoes = 2 shoes
1 dozen mittens = 12 mittens
1 pair of mittens = 2 mittens.

"mole" is the exact same concept.  It is a label for a quantity just like dozen and pair except the number is different.  Instead of 12 or 2... 1 mole = 602,200,000,000,000,000,000,000 of anything (to 4 sig figs) which we usually write in scientific notation as 6.022x10^23 to prevent degenerative eye disease and insanity.

so..
1 dozen donuts = 12 donuts
1 mole of donuts = 6.022x10^23 donuts
1 pair of donuts = 2 donuts

likewise
1 dozen Cu atoms = 12 Cu atoms
1 mole of Cu atoms = 6.022x10^23 Cu atoms..
1 dozen H2 molecules = 12 H2 molecules
1 mole O2 molecules = 6.022x10^23 O2 molecules

and of course
2 dozen CH4 molecules = 2x12 = 24 CH4 molecules
2 moles of CH4 molecules = 2x6.022x10^23 = 12.044x10^23 CH4 molecules

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seems easy right?  So what makes this so difficult?  2 things.. (1) molar vs molecular vs atomic mass, and (2) conversational chemistry language.   I'll try to cover both in the remaining characters.

The easiest way to get a handle on molar vs atomic mass is to look on a periodic table and read the mass as AMU / atom.

example.  copper..
atomic mass = 63.55 AMU / atom

now.. because of the way AMU and MOLE are defined..
1 AMU = 1.66x10^-24g
1 mole of atoms = 6.022x10^23 atoms
and if you notice 1 / 6.022x10^23 = 1.66x10^-24

we can easily show that
1 AMU / atom = 1gram / 6.022x10^23 atoms = 1g / mole of atoms

get that? the numbers are the same.   the units are NOT!!!.  one is mass PER ATOM.. the other is mass per MOLE OF ATOMS.  mass per 6.022x10^23 atoms.   one has mass units of AMU, the other GRAMS.  the numbers work out to be the same because of the way we define AMU and MOLE.  This allows us to read mass on a periodic table as AMU/atom AND as g/mole of atoms

example.. copper
atomic mass = 63.55 AMU / atom
molar mass = 63.55 g / mole of atoms

methane.. CH4
molecular mass = 1x12.01 +4x1.008 = 16.04 AMU / molecule
molar mass = 16.04 g/mole of molecules

notice how I keep writing g/mole "of atoms" and "of molecules"?.. That is the conversational part.  chemistry is like a foreign language.  and like all foreign languages we have a conversational part.  And we tend to leave of "of atoms" and "of molecules" and assume the world knows what we mean.

example.. carbon.
atomic mass = 12.01 AMU / atom
molar mass = 12.01 g/mole.... . mole "of atoms" is understood

ethane.. C2H6
molecular mass = 2x12.01 +6x1.008 = 30.07 AMU / molecule
molar mass = 30.07 g/mole... .. mole "of molecules" is understood.. i.e.. 30.07g / 6.022x10^23 molecules

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to answer your question...
1 mol = 6.022x10^23 units
avogadros number = 6.022x10^23

comparing..
a sample containing 1 mole of a substances has avogadros number of particles in that sample.
 
contrasting..
mole is a label for a quantity of substances
avogadros number is a number.
an exact analogy is mole is to avogadros number as dozen is to 12