Message text written by toad
>Brethren
It is all well and good to mention a significant truism as Avgrado's
Number, but, "What does this number represent?"
Toad
<
Welcome to Chemistry 101. It is the number of molecules in a mole. What
does that mean? Well , one mole of a substance weighs, in grams, the total
of molecular weights. In other words one mole of helium gas weighs 4 grams
(the molecular weight of helium is 4) and a mole of water weighs (16+1+1)
18 grams.
Additionally, one mole of gas occupies 22.4 litres of space at STP
(standard temperature and pressure which is defined at 20 deg C and one
atmosphere). It is this effect that explains how dirigibles fly. If you
fill an envelope with Helium the one mole of helium weighs less than the
one mole of air (Nitrogen and oxygen) it displaces.
What does this have to do with LBC's? Nothing but don't forget PV=nRT.
Dave
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