1. MASS and MOLES
Page 57 of INB

2. How many particles are in one mole of Fe?
Essential Question:
How many particles are in one mole of Fe?

3. Atomic Mass:
A single fluorine atom is less then 1 trillionth of a billionth of a gram.
Because these numbers are so small we express mass as a unified atom mass.
Or 1/12th the mass of a carbon 12 atom (amu = atomic mass unit).
Atomic mass is a weighted average, with more common isotopes having a greater effect on the atomic mass.

4. Mole:
1 Mole (mol) = 6.02 x 1023 particles = Avogadro's number
The number of atoms in 12g of carbon-12.
So, Moles and grams are related.
The mass in grams of 1 mole of a substance is called its molar mass.
1 mol Carbon-12 = g,
So, molar mass = g/mol.

5. Mole:
In nature the elements occur as a mixture of all the different isotopes.
An elements Molar mass in grams/mole is equal to the average atomic mass.
Molar mass = atomic mass expressed in grams

6. Conversions: mol to g (use periodic table)
You can use the molar mass to convert between moles, grams, and atoms.
6.0 mol F = _____ g F
199.75g Br = ____ mol Br

7. More examples: (mol to atoms use Avogadro's number)
2.0 mol C = _____ atoms C
3.01 x 1023 atoms Cl = _____ mol Cl

8. Now the hard ones. (g to atoms, must stop at moles)
g Al = _____ Atoms Al
1.51 x 1023 atoms Na = _____ g Na

9. 37.0 mol Ruthenium = _____ g Ru 1.3 moles Pb = _____ atoms Pb
Practice: page 59
15.3 g He = _____ mol He
37.0 mol Ruthenium = _____ g Ru
1.3 moles Pb = _____ atoms Pb
2.41 x 1023 atoms Cr = _____ mol Cr
1.51 x 1023 atoms K = ____ g K
g Cu = ____ atoms Cu