1. What is a Mole? (watch the video)

2. Collection Terms
1 trio = 3 singers 1 six-pack Cola = 6 cans Cola drink 1 dozen donuts = 12 donuts 1 gross of pencils = 144 pencils

3. A Moles of Particles Contains 6.02 x 1023 particles
1 mole C = x 1023 C atoms
1 mole H2O = x 1023 H2O molecules
1 mole NaCl = x 1023 Na+ ions and
6.02 x 1023 Cl– ions

4. Examples of Moles
Moles of elements 1 mole Mg = 6.02 x 1023 Mg atoms 1 mole Au = 6.02 x 1023 Au atoms Moles of compounds 1 mole NH3 = 6.02 x 1023 NH3 molecules 1 mole C9H8O4 = 6.02 x 1023 aspirin molecules

5. 6.02 x 1023 particles 1 mole or 1 mole
Avogadro’s Number
6.02 x 1023 particles 1 mole or 1 mole

6. Amedeo Avogadro

9. Molar Mass Number of grams in 1 mole
Equal to the numerical value of the atomic mass
1 mole of C atoms = g
1 mole of Mg atoms = 24.3 g
1 mole of Cu atoms = 63.5 g

10. Learning Check
Give the molar mass to 0.1 g A. 1 mole of Br atoms = ________ B. 1 mole of Sn atoms = ________

11. Solution
Give the molar mass to 0.1 g A. 1 mole of Br atoms = 79.9 g/mole B. 1 mole of Sn atoms = g/mole

12. Molar Mass of Compounds

13. Molar Mass of Compounds
Mass in grams of 1 mole equal numerically to the sum of the atomic masses
1 mole of CaCl2 = g/mole
1 mole Ca x 40.1 g/mole
+ 2 moles Cl x 35.5 g/mole
1 mole of N2O4 = 74.0 g/mole
2 moles N x 14.0 g/mole
+ 4 moles O x 16.0 g/mole

14. Learning Check
A. 1 mole of K2O = ______g B. 1 mole of antacid Al(OH)3 = ______g

15. Solution
A. 1 mole of K2O = 94.2 g 2 K x 39.1 g/mole + 1 O x 16.0 g/mole B. 1 mole of antacid Al(OH)3 = 78.0 g 1 Al x 27.0 g/mole + 3 O x 16.0 g/mole + 3 x 1.0

16. Learning Check
Prozac, C17H18F3NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. It has a molar mass of
1) g/mole
2) 262 g/mole
3) 309 g/mole

17. Solution
Prozac, C17H18F3NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. It has a molar mass of
3) 309 g/mole
17C (12.0) + 18H (1.0) + 3F (19.0) + 1N (14.0) + 1 O (16.0)

18. Gasses are weird…

19. Mass, Volume, Mole Relationship

20. Welcome to Mole Island 1 mol = molar mass 1 mole = 22.4 L @ STP
6.02 x 1023 particles

21. Stoichiometry Island Diagram
Known Unknown
Substance A Substance B M
Mass
Mass Mountain
Mass
Mole Island
Volume
Mole
Mole
Volume V
Liter Lagoon
Particles
Particles P
Particle Place
Stoichiometry Island Diagram

22. Stoichiometry Island Diagram
Known Unknown
Substance A Substance B M
Mass
Mass Mountain
Mass
Volume
Mole
Mole
Volume V
Liter Lagoon
Particles
Particles P
Particle Place
Stoichiometry Island Diagram

24. Stoichiometry Mole Island Diagram When in doubt…convert to moles!
Known Unknown
Substance A Substance B
Mass
Mass
1 mole = molar mass (g)
1 mole = molar mass (g)
Use coefficients
from balanced
chemical equation
Volume
Mole
Mole
Volume
1 mole = STP
1 mole = STP
(gases)
(gases)
1 mole = x 1023 particles
(atoms or molecules)
1 mole = x 1023 particles
(atoms or molecules)
Particles
Particles

25. A. Using Mole Island Zn + 2HCl  ZnCl2 + H2 79.1 g ? L 79.1 g Zn 1 mol
Just watch, don’t write: If you have 79.1 g of Zn to react with excess HCl (enough HCl to keep reacting as long as you need), how many Liters of H2 gas will be produced?
Zn HCl  ZnCl H2
79.1 g
? L
79.1
g Zn
1 mol Zn
65.39
g Zn
1 mol H2 Zn
22.4 L H2
1 mol
= 27.1 L H2

26. B. Using Mole Island Zn + 2HCl  ZnCl2 + H2 ? L 79.1 g 79.1g HCl 1 mol
Now write this one for practice: If you instead have 79.1 g of HCl to react with excess Zinc (enough Zinc to keep reacting as long as you need), how many Liters of H2 gas will be produced?
Zn HCl  ZnCl H2
? L
79.1 g
79.1g HCl
1 mol
HCl
36.5g HCl
1 mol H2
2 mol
HCl
22.4 L H2
1 mol
= 24.3 L H2

27. Zn + 2HCl  ZnCl2 + H2 79.1 g 79.1 g HCl 1 mol HCl 36.5 g Zn 1 mol H2
Other possibilities: Still starting with 79.1 grams of HCl, how many molecules of H2 gas are produced? Or what mass of H2 gas is produced? How would these questions change your calculations?
Zn HCl  ZnCl H2
79.1 g
? mc
Or ? g
Same conversion to moles, same mole to mole ratio, different last conversions…
79.1
g HCl
1 mol
HCl
36.5
g Zn
1 mol H2
2 mol
HCl
6.02 x 1023 mc H2
1 mol H2
= 6.5 x 1023 mc H2
= 2.17 g H2