How many mols of aluminum atoms are in 1.42 xx 10^241.42×1024 atoms?
Am I doing this right?
1.42x1024 x 26.98 = 3.83x1025
Am I doing this right?
1.42x1024 x 26.98 = 3.83x1025
1 Answer
What you did was multiply the molar mass of aluminum atom by the number of atoms, which physically doesn't make sense; it gives you:
"g"/"mol" xx "atoms" = ("g"cdot"atoms")/"mol"gmol×atoms=g⋅atomsmol .
The atoms "unit" has to cancel so that you get into the units of
cancel("atoms") xx "mol"/cancel("atoms")
How I would do it is to recall that
So if you have
That's just an estimate, but it gives you an idea of what we expect to get.
1.42xx10^24 cancel"atoms" xx "1 mol"/(6.022xx10^23 cancel"atoms") = 14.2/6.022 = bb("2.36 mols") of aluminum atoms.
A
Similarly,