Usually, a student gets doubts like: how Avogadro number was arrived at?, Why atomic mass is dimensionless? How do you measure molar mass of an molecular substance, etc. These have nicely been explained here:
http://digipac.ca/chemical/molemass/index.htm
The contents are given below:
Atomic weight?
So what is the unit for atomic mass?
An analogy for atomic mass
-An "atomic weight" experiment
-Avogadro's Hypothesis
The Relative Masses of Gases - a demonstration experiment
So then, why isn't the atomic mass of Hydrogen exactly 1?
-Isotopes
-Who picked hydrogen, anyway?
What, you say? Not a molecule?
Calculating formula masses
Of Moles and other furry creatures
How many is that? Does it matter? It's enough!
-Where'd they get that number?
Summary - Molar Mass
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