CHEMISTRY COMMUNITY

So is Avogadro's Number used only when converting from moles to atoms or can it be used to convert from moles to molecules as well?

I believe avogadro's number can be used to convert both from moles to atoms and from moles to molecules.

Yes, it can be used to convert from moles to molecules as well (1 mole= 6.022 × 10^23 molecules). I think it depends on the basic units of the substance; whether it's atoms or molecules.

Yes it can be used for both and it does depend on the basic units of the substance.

Hi Kate,
Avagadros number is used to find the amount of blank in blank. It can be applied to the number of atoms in an element, the number of molecules in a compound, and even the amount of formula units in an ionic compound.

It can be used both ways, as long as it is applied correctly (multiplying by it when going from moles to atoms and dividing when going from atoms to moles)

So when asked for atoms of a molecule we can multiply by the mols by Avogadro's number to get number of atoms, but I do not understand how to get molecules from mols?

Jchellis 1I wrote:So when asked for atoms of a molecule we can multiply by the mols by Avogadro's number to get number of atoms, but I do not understand how to get molecules from mols?

You can do the same thing to get molecules, because moles is just a unit of "something" not just an atom, but also molecules or formula units. So you would multiply the amount of moles of the molecule you are looking at by Avogadro's number, to get the number of molecules.

would you use the inverse if you're going in the opposite direction?

can someone clarify what would it be for :
- atoms to moles
- moles to atoms

thank you

Yes, because Avogadro's number is used as a conversion factor, it is reversible.

So, going from "x" atoms to moles, you would say "x" atoms times (1 mol/6.022 x 10²³ atoms) = y mol.
Let's say you have 15 atoms. 15 atoms x (1 mol/6.022 x 10²³ atoms) = 2.5 x 10^-23 mol.

Alternatively, going from "x" moles to atoms, you would say "x" moles" times (6.022 x 10²³ atoms/1 mol) = y atoms.
So here, as an example, we might have 11 mol. 11 mol x (6.022 x 10²³ atoms/1 mol) = 6.6 x 10²⁴ atoms.

To sum again, you can use the inverse to solve a problem, just make sure there is cancellation of units.

Suppose you want to convert 3 moles of O to atoms.


Likewise, if you want to convert 1.806*10^{24}[/tex] atoms to moles, you do the opposite.


You could look at it as the inverse to go in either direction, but it may be simpler to think of using Avogadro's number to cancel out units to convert into another set of units.

Does Avogadro's number include units, or do we use the number alone?