How do you calculate atoms of an element?

To calculate the number of atoms of an element, you can use Avogadro's number and the given quantity of the substance. Avogadro's number is a fundamental constant that represents the number of entities (atoms, molecules, ions, etc.) in one mole of a substance. It is approximately
6.022
×
1
0
23
6.022×10
23
entities per mole.

The formula to calculate the number of atoms is:

Number of atoms
=
Quantity of substance
×
Avogadro’s number
Number of atoms=Quantity of substance×Avogadro’s number

For example, if you have 2 moles of carbon atoms, you can calculate the number of atoms using Avogadro's number:

Number of atoms
=
2
 
moles
×
(
6.022
×
1
0
23
 
atoms/mole
)
Number of atoms=2moles×(6.022×10
23
atoms/mole)

Number of atoms
=
1.2044
×
1
0
24
 
atoms
Number of atoms=1.2044×10
24
atoms

Make sure to use the appropriate units and Avogadro's number for the substance you are working with. If you have a mass of the substance instead of moles, you can use the molar mass (mass of one mole) of the substance to convert from mass to moles before using the above formula.