1. Do now
Pick up notes.
Get out your calculator and green periodic table.
Lab is due Tuesday.

2. Also called Avogadro’s Number
THE MOLE
 The MOLE (mol) is the unit of measurement that describes the amount of matter in a particular substance.
1 mole = x 1023 particles
= x 1023 particles
(particles are atoms, formula units, or molecules)
Also called Avogadro’s Number
This is a rounded number.
Just like a DOZEN describes 12 and a GROSS describes A mole of eggs is 6.02 x eggs.

3. THE MOLE
Vmg

4. THE mole
Disc 4 Chapter 20
VISUALIZING MOLES

5. HOW big is a mole?
The number of milliliters of water in the Pacific Ocean is nearly equal to Avogadro’s number.
An Avogadro’s Number of rice grains would weigh as much the total of all cars if every person on earth owned a million cars.
If there were one mole of people, it would take 120 trillion earths, each with today’s population, to accommodate them.
If grains of sand were laid to cover the entire state of Texas, a mole of sand that covers the state would be have to be 50 feet tall.

6. CALCULATING MOLES
When looking at a compound of say, AlCl3 we could say the following:
“In one mole of AlCl3, there are one mole of Al and three moles of Cl.”
So if there are 3.0 moles of AlCl3, how many moles of Cl are there?

7. Moles to moles
These kinds of problems involve making a comparison of one item to another.
You must be able to count atoms.
In one formula unit of Ca(OH)2, there is one atom of Ca, two atoms of O, and two atoms of H.
In one mole of Ca(OH)2, there is one mole of Ca, two moles of O, and two moles of H.

8. Moles to moles
How many moles of hydroxide ions are in moles of Ca(OH)2?
2.50 mol Ca(OH) mol OH-1 = 5.00 mol OH-1
1 mol Ca(OH)2
Always start with what you are given.
Then find the conversion factor that gets you the desired outcome.

9. Moles to moles
2. Determine the number of moles for carbon, hydrogen and oxygen if you have 3.00 moles of C6H12O6.

10. The mole and mass
The mole is a conversion factor that relates the number of particles of matter to the matter’s mass.
We use the MOLAR MASS which comes from the periodic table.
Molar mass = mass (g) of one mole of atoms.
 We can say that 1 mole of Na is 22.99g which is x 1023 atoms Na.
Now you do it for Magnesium.
___________ mol Mg = ______________ g Mg
= ____________________ atoms Mg

11. MOLES AND MASS
We will use dimensional analysis (factor label) to make mole/mass conversions.
Use the conversion factor:
atomic
molecular MASS (amu) = MOLAR (g) = 1 MOLE
formula MASS

12. PRACTICE
Always start with the number you are given and then find the conversion factor that gets you to the desired outcome.
A. Calculate the mass in grams of 2.0 moles of Na.
??g = 2.0 mol Na g Na = g Na
1 mol Na

13. practice
B. Calculate the mass in grams of moles of CO2

14. practice You can also calculate the number of moles in a given mass.
C. How many moles are in 50.0 g of H2?
?? moles = 50.0 g H mole H2 = mol H2
2.02g H2

15. practice
D. How many moles are in 75.0 g of NaOH?

16. MOLES AND PARTICLES
We use factor label to make mole/particles conversions.
Use the conversion factor:
1 mole = 6.02 x 1023 particles
(particles are atoms, formula units, or molecules)

17. practice
A. Determine the number of molecules in 2.23 moles of nitrogen, N2. ?? molecules = 2.23 mol N2 6.02x1023 molecules N2 1 mol N2 = molecules N2

18. practice
B. Determine the number of atoms in moles of sulfur.

19. practice
C. Determine the number of moles in 4.36 x atoms of silver, Ag
?? Moles
= 4.36 x 1024 atoms Ag mol Ag
6.02 x 1023 atoms Ag

20. practice
D. Determine the number of moles in 2.50 x molecules of H2O.

21. TO DO Complete the Mole City, Part One handout for tomorrow.
Be sure to write the units and substance for every number.
The answer should be written with the correct number of significant figures and have units and substance listed.

22. FIRST ONE ON HOMEWORK
1. Find the number of moles of the chloride ion, Cl-, in 5.00 moles NaCl.