N_A always gets me.
6.022E23 molecules/mole.
An absolutely staggeringly large number.
Yet you hold it in your hand when you hold 18 grams (a little over 1 tablespoon) of water.
There are estimates of the number of stars in the observable universe that are in the 1E23 range... http://www.universetoday.com/36302/
We are so incredibly, mind-bogglingly tiny in the even local scheme of things - no wonder that so many "religious" people are anti-science.
:-(
They're missing out on the wonder of it all. ;-)
Cheers,
Scott.