## Avogadro's Number [ENDORSED]

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Kate Manganaro 1F
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Joined: Fri Apr 06, 2018 11:03 am

### Avogadro's Number

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?

Heung Ching Chia 1E
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Joined: Mon Apr 09, 2018 1:38 pm

### Re: Avogadro's Number

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

octaviahuang1f
Posts: 30
Joined: Fri Apr 06, 2018 11:03 am

### Re: Avogadro's Number

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.

tmehrazar
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Joined: Fri Apr 06, 2018 11:04 am

### Re: Avogadro's Number  [ENDORSED]

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

Mohamad 1J
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Joined: Mon Apr 09, 2018 1:39 pm

### Re: Avogadro's Number

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.

Luis Torres 1C
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### Re: Avogadro's Number

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)

Jchellis 1I
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Joined: Fri Sep 28, 2018 12:15 am

### Re: Avogadro's Number

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?

904936893
Posts: 62
Joined: Fri Sep 28, 2018 12:29 am

### Re: Avogadro's Number

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.

Shibhon_Shepard
Posts: 62
Joined: Wed Nov 15, 2017 3:04 am

### Re: Avogadro's Number

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

Jeremy_Guiman2E
Posts: 82
Joined: Fri Sep 28, 2018 12:29 am

### Re: Avogadro's Number

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.

Chem_Mod
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### Re: Avogadro's Number

Suppose you want to convert 3 moles of O to atoms.
$\frac{3 moles}{1} * \frac{6.022*10^{23}atoms}{1 mole} = 1.806*10^{24}atoms$

Likewise, if you want to convert 1.806*10^{24}[/tex] atoms to moles, you do the opposite.
$\frac{1.806*10^{24} atoms}{1}*\frac{moles}{6.022*10^{23}atoms} = 3 moles$

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.

Nicolette_Canlian_2L
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### Re: Avogadro's Number

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

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