1. The Mole and Molar Mass

2. The Mole 1 dozen = 12 eggs 1 ream = 500 sheets of paper
1 hat trick = 3 goals
1 mole = x 1023 atoms (or ANYTHING!)
Or 602,200,000,000,000,000,000,000 atoms
Also known as “Avogadro’s number”

3. The Mole 1.0079 g of H contains 6.022 x 1023 atoms
g of C contains x 1023 atoms
g of O contains x 1023 atoms
g of Au contains x 1023 atoms
g of Ca contains x 1023 atoms
See the pattern?

4. The Mole 6.022 x 1023 atoms (or molecules) / mol
molar mass: the atomic weight (in grams) is the mass of one mole of that element
We can also find the molar mass of compounds by ADDING the molar masses of each element
Molar masses have units of g/mol
Note: units on Avogadro’s # are
6.022 x 1023 atoms (or molecules) / mol

5. Molar Mass Example
What is the molar mass of calcium hydroxide, Ca(OH)2?

6. Example
How many moles does a 25.2 gram sample of CaCl2 contain?

7. Example
How many moles of silver are equivalent to x 1015 atoms?

8. Example
What is the mass of x 1020 magnesium atoms?