1. The Mole

2. What is a mole?
A conversion factor we use in chemistry to make it easier to talk about a very large amount of particles of elements or compounds
1 dozen bagels = 12 bagels
1 mole bagels = 6.02 x 1023 bagels

3. Avogadro’s Number Avogadro’s # = 6.02 x 1023 units
How does this number relate to a mole?
1 mole = 6.02 x 1023 units
*Units can be anything but in chemistry these units are referred to as:
Particles
Atoms
Molecules
Formula Units

4. How big is 6.02 x 1023?
Astronomers estimate that there is a mole of stars in the Universe.
One mole of high school textbooks would cover the USA to a depth of about 300 Km.
One mole of marshmallows would cover the USA to a depth of Km.
One mole of moles placed to head to tail would stretch 11 million light years and weigh 9/10 as much of the moon.
One mole of pennies would make at least seven stacks that would reach the moon.
One mole of watermelon seeds would be found inside a melon slightly larger than the moon.

5. Examples 1 mole Fe = 6.02 x 1023 atoms Fe
1 mole C12H22O11 = 6.02 x 1023 molecules C12H22O11
1 mole Al = 6.02 x 1023 atoms Al
1 mole BeF2 = 6.02 x 1023 formula units BeF2

6. Moles Particles Conversion
Remember… 1 mol = 6.02 x 1023 units
Units in chemistry are atoms, molecules, formula units, particles

7. Moles To Particles
How many atoms of carbon make up 6.80 moles of carbon?
6.80 mol C
6.02 x 1023 atoms C
4.09 x 1024 atoms C
1 mol C

8. Moles To Particles
How many formula units of potassium phosphate make up 1.3 moles?
1.3 mol K3PO4
6.02 x 1023 f.u. K3PO4
7.8 x 1023 f.u. K3PO4
1 mol K3PO4

9. Moles To Particles 2 moles of carbon dioxide = ? molecules 2 mol CO2
6.02 x 1023 molecules CO2
1 x 1024 molecules CO2
1 mol CO2

10. Particles To Moles How many moles make up 5.60 x 1025 atoms of copper?
5.60 x 1025 atoms Cu
1 mol Cu
93.0 mol Cu
6.02 x 1023 atoms Cu

11. Particles To Moles
How many moles make up 6.3 x 1023 formula units of ammonium nitride?
6.3 x 1025
f.u. (NH4) 3N
1 mol (NH4) 3N
1.0 x 102 mol (NH4) 3N
6.02 x 1023

12. Particles To Moles 25 molecules of carbon tetrahydride = ? moles
25 molecules CH4
1 mol CH4
4.2 x mol CH4
6.02 x 1023
molecules CH4

14. How is the mole measured in the lab?
It is impossible to count up individual particles of chemicals in the lab because of their small size
We must find another way to measure 6.02 x 1023 particles of a substance

15. How does mass relate to the mole?
What does an amu (atomic mass unit) measure?
1 amu = × kilograms
A relative scale used to measure the mass of single elements or compounds

16. Learning the termonology… Atomic Mass
Atomic Mass - measures the mass of a single atom in amu’s
Example: 1 atom Fe = amu
*Always go to the hundredths place when taking measurements from the periodic table

17. Formula Mass
Formula Mass - measures the mass of a single formula unit (ionic compound) in amu’s
Example: 1 formula unit BeF2 =
1Be 9.01 amu +
2F 2(19.00 amu) = amu

18. Molecular Mass
Molecular Mass - measures the mass of a single molecule in amu’s
Example: 1 molecule C12H22O11 =
12 C atoms 12(12.01 amu) +
22 H atoms 22(1.01 amu) +
11 O atoms 11(16.00 amu) = amu

19. Molar Mass The mass of 1 mole of any substance in grams Example:
1 atom Fe = amu
1 mole (6.02 x 1023 atoms) Fe = g
1 molecule C12H22O11 = amu
1 mole (6.02 x 1023 molecules) C12H22O11 = g

20. What is a representative particle?
The smallest particle that represents the true identity of the entire substance without altering it’s characteristics or properties
Example: What is the representative particle of 52 Al atoms?

21. Answer: 1 atom Al Example: What is the representative particle of 1 molecule of BeF2?

22. Answer: 1 molecule BeF2
1 atom of Be or 1 atom of F would not truly represent the properties and characteristics of BeF2

23. Moles Grams Conversion
Remember… molar mass can be used as a conversion for any type of particle
12.01 grams C = 1 mole C
58.44 grams of NaCl = 1 mole NaCl
44.01 grams of CO2 = 1 mole CO2

24. Moles To Grams How many grams is 4.672 mol barium chloride?
1 mol BaCl2 = g BaCl2
4.672 mol BaCl2
g BaCl2
972.9 g BaCl2
1 mol BaCl2

25. Grams To Moles .0025 g disulfur trioxide = ? mol
1 mol S2O3 = g S2O3
.0025 g S2O3
1 mol S2O3
2.2 x 10-5 mol S2O3
g S2O3

27. Grams Particles Converting
This is a 2-step process. You must ALWAYS go through the mole first.

28. Grams To Particles
How many atoms of platinum are needed to obtain g?
g Pt = 1 mol Pt
1 mol Pt = 6.02 x 1023 atoms Pt
15.00 g Pt
1 mol Pt
6.02 x 1023 atoms Pt
4.629x 1022
atoms Pt
g Pt

29. Particles To Grams
What is the mass of 2.77 x 1013 molecules of oxygen?
32.00 g O2 = 1 mol O2
1 mol O2 = 6.02 x 1023 molecules O2
2.77 x 1013
molecules O2
1 mol O2
32.00 g O2
1.47 x 10-9 g O2
6.02 x 1023

30. Liters Moles Conversion
Liters (L) are a volume unit of measurement
STP = standard temperature and pressure conditions (0°C and 1 atm)
This conversion only may be used when:
At STP conditions
Working with gases
1 mole = 22.4 L of STP

31. Liters To Moles
How many moles of chlorine STP take up 4.9 L of space?
4.9 L Cl2
1 mol Cl2
.22 mol Cl2
22.4 L Cl2

32. Mole To Liters
How much space does moles of carbon monoxide gas take STP?
.0359 mol CO
22.4 L CO
.804 L CO
1 mol CO

33. Liters Particles Converting
This is a 2-step process. You must ALWAYS go through the mole first.

34. Liters To Particles
How many molecules of iodine gas take up 3.56 L of STP?
1 mole = 22.4 L of STP
1 mole = 6.02 x 1023 particles
3.56 L I2
1 mol I2
6.02 x 1023 molecules I2
9.57 x 1022 molecules I2
22.4 L I2

35. Particles To Liters
How much space does 3.5 x 1022 molecules of nitrogen dioxide gas take STP?
1 mole = 22.4 L of STP
1 mole = 6.02 x 1023 particles
3.5 x 1022 molecules NO2
1 mol NO2
22.4 L NO2
1.3 L NO2
6.02 x 1023 molecules NO2

36. Liters Grams Converting
This is a 2-step process. You must ALWAYS go through the mole first.

37. Liters To Grams What is the mass of .57 L of hydrogen gas @ STP?
1 mole = 22.4 L of STP
1 mole = 2.02 g H2
.57 L H2
1 mol H2
2.02 g H2
.051 g H2
22.4 L H2

38. Grams To Liters
How much space does 5 x 105 g of water vapor take STP?
1 mole = 22.4 L of STP
1 mole = g H2O
5 x 105 g H2O
1 mol H2O
22.4 L H2O
6 x 105 L H2O
18.02 g H2O