
- Knowing the number of moles allows you to calculate the number of atoms if you are dealing with chemical compounds.
- Moles are very useful, they allow chemists to use chemical equations to determine the mass of reactants and products.
Read about Avogadro Constant
Example
How many moles in 1000 g of C12H22O11 (sugar)?
Solution:
Step 1: Molar mass = 12(12.01) + 22(1.008) + 11(16) = 342.296g/mol
Step 2: n = m/mm = 1000g/342.296g per mol = 2.92 moles (rounded)
Atomic mass from the periodic table
Elements | Symbol | Atomic Mass |
Hydrogen | H | 1.00794 |
Carbon | C | 12.0107 |
Oxygen | O | 15.9994 |