## What exactly is Avogrado's Number? [ENDORSED]

emmajanibekyan_4I
Posts: 17
Joined: Wed Sep 21, 2016 2:57 pm

### What exactly is Avogrado's Number?

I'm still a little bit confused on when it's the appropriate time to use Avogrado's constant in a problem. Can somebody give me an example, and define why it is necessary?

Swati_Sharma_2D
Posts: 21
Joined: Wed Sep 21, 2016 2:59 pm

### Re: What exactly is Avogrado's Number?  [ENDORSED]

Generally, Avogadro's number is used when a problems asks for how many atoms/molecules/formula units of a certain element or substance there are. In that case, you can use stoichiometry to find the number of units because there are 6.022 x 10^23 units per mole.

For example, say you were given a problem where it says there is 1.00 gram of carbon and to find the number of atoms in that sample. In order to solve this problem you would stoichiometry as follows:

1.00 gram C x (1 mole C/12.01 g C) x (6.022 x 10^23 atoms C/1 mole C) = 5.01 x 10^22 atoms C

So, Avogadro's number is necessary when we wish to find the number of atoms/molecules/formula units/etc. something has.