1. Avogadro, The Mole, and Grams
HAHS
Mrs. Taylor
Avogadro, The Mole, and Grams

2. The Mole
The amount of substance that contains as many particles as there are atoms in exactly 12 g of carbon.
We can think of the mole is a counting unit for chemists.
Examples:
1 dozen =12
1 ream of paper = 500 sheets

3. I didn’t discover it. Its just named after me!
Avogadro’s Number
Is the number of particles in exactly one mole of a pure substance.
6.02 x 1023 is called “Avogadro’s Number” in honor of the Italian chemist Amadeo Avogadro ( ).
I didn’t discover it. Its just named after me!

4. Avogadro’s Number (con’t)
There is atoms in 1 mole of a substance
THAT’S A GIGANTIC NUMBER!!!!!!!!!

5. Molar Mass Is the mass of 1 mole of a per substance
Has units of grams per mole (g/mol)
Equaled to the atomic mass of the element or compound.

6. Molar Mass of a Compound
Add up all the masses of each type of atom in the compound.
Example: Molar Mass of Ca(OH)2
Ca: 1 x 40 = 40
O: 2 x 16 = 32 The molar mass is the H: 2 x 1 = sum ( ) which is equaled to 74 g/mol

7. Molar Mass Is the mass of 1 mole of a per substance
Has units of grams per mole (g/mol)
Equaled to the atomic mass of the element or compound.

8. Calculations: Converting moles to grams
Given # of mole X g (look at periodic table)= g of
1 mole
How many grams of lithium are in 3.50 moles of lithium?
3.50 mole X g = g Li
1 mol

9. Calculations: Converting grams to moles
Given # of g X mol = mol of
g (look at periodic table)
How many moles of lithium are in 18.2 grams of lithium?
18.2 g X 1 mol Li = mol Li
6.941 g

10. Calculations: Converting Moles to Particles
Given # of mol x 6.02 x 1023 part= atoms
1 mol
How many atoms/particles/molecules of lithium are in 3.50 moles of lithium?
3.50 mole X 6.02 x = x 1024 atoms of Li

11. Calculations: Converting Particles to Moles
Given # of particles x 1 mole = mol
6.02 x 1023
How many moles of lithium are there in x particles of Li?
x 1024 part x 1 mole = mol Li
6.02 x 1023 part

12. Calculations: Converting grams to particles
Given # of grams x 1 mol x x 1023= particles
? g mol
How many atoms/particles/molecules of lithium are in 18.2 g of lithium?
18.2 g x 1 mol x x 1023 = x 1024 particle Li
6.941g mol

13. Calculations: Converting particles to grams
Given # of particles x 1 mol x ? g = g
6.022 x mol
How many grams are there in 8.02 x 1025 particles of lithium?