2. “Moles”

3. MOLE  is a way of translating between grams and amu’s
a mole is a number that helps us translate between the atomic world and our every day world
specifically  “6.02 x 1023”
known as:
“Avogadro’s Number”

4. MOLE  is a direct translation 1 mole of an atom’s amu = 1 g
between grams and amu’s
1 mole of an atom’s amu = 1 g
1 gram = 6.02 x 1023 amu = 1 mole
(e.g.) carbon-12 [12C] = 12 amu
12 amu = 6.02 x 1023 of carbon atoms
6.02 x 1023 of 12C = 12 grams
1 gram of 12C = 1 mole of 12C

5. Fe MOLES and GRAMS 1 mole of an atom’s amu = 1 g
1 gram = 6.02 x 1023 amu = 1 mole
Fe = = 56 amu
56 amu = [56Fe]
56 amu x 6.02 x 1023 = 1mole
1 mole of 56Fe = 56 g 26 Fe
iron
55.85

6. Si 28 MOLES and GRAMS 1 mole of an atom’s amu = 1 g
1 gram = 6.02 x 1023 amu = 1 mole
Si = = 28 amu
28 amu = [28Si]
28 amu x 6.02 x 1023 = 1mole
1 mole of 28Si = ___ g 14 Si
silicon
28.09 28

7. Si 56 MOLES and GRAMS 1 mole of an atom’s amu = 1 g
1 gram = 6.02 x 1023 amu = 1 mole
Si = = 28 amu
28 amu = [28Si]
28 amu x 6.02 x 1023 = 1mole
2 moles of 28Si = ___ g 14 Si
silicon
28.09 56

8. O 64 16 MOLES and GRAMS 1 mole of an atom’s amu = 1 g
1 gram = 6.02 x 1023 amu = 1 mole
O = = ___ amu
16 amu = [16O]
16 amu x 6.02 x 1023 = _ mole
4 moles of 16O = ___ g 8 O
oxygen
15.999 16 1 64

9. MOLAR MASS Molar Mass is measured in grams per mole (g/mol)
EQUALS the MASS of “1” MOLE of a substance
it is the MASS of “1” MOLE of a single TYPE OF ATOM (an element)
if the substance consists of a molecule, the molar mass is the MASS of each individual atom in that molecule / compound
Molar Mass is measured in grams per mole (g/mol)

10. Molecular Mass is measured in grams per mole (g/mol)
is the combined MASS of the group of atoms forming a SINGLE MOLECULE (smallest unit of a compound)
FIND by “adding” the MASSES of the atoms forming the molecule
Molecular Mass is measured in grams per mole (g/mol)

11. GRAMS per MOLE
g/mol  how the number of GRAMS of “1” MOLE of any substance would feel
(e.g.)
Molecular Mass of CO2 = 44 g/mol
EXPLANATION:
If you had “1” mole of a CO2 molecule, its mass would be 44 g (the feel of “44” USA dollar bills stacked in your hand)

12. MASS in AMU 12C = 1 mole = 6.02 x 1023 12C = 12 amu = 12 g/mol = 12 g
you can express the MASS of an ATOM (ELEMENT) or a single molecule (COMPOUND) in AMU (atomic mass units)
(e.g.) 12C = 12 amu = 1 mole
12C = 1 mole = 6.02 x 1023
12C = 12 amu = 12 g/mol = 12 g

13. FINDING MOLECULAR MASS:
1st  look up the Average Atomic Masses of the molecule’s component ELEMENTS on the Periodic Table
2nd  round each Average Atomic Mass to the nearest WHOLE number
3rd  use the ATOMIC MASS of each ATOM per ELEMENT in the COMPOUND
4th  find the TOTAL SUM

14. C O EXAMPLE – Finding Molecular Mass C = 12.01 = 12 amu
in AMU:
CO2
C = = 12 amu
O = = 16 amu
CO2 = 1 (C atom) (O atoms)
CO2 = 1 (12 amu) (16 amu)
CO2 = 12 amu amu
CO2 = 44 amu 6 C
carbon
12.01 8 O
oxygen
15.999

15. CONVERTING amu to g/mol:
seldom refer to MOLECULAR MASS in amu units, but rather in g/mol
to convert amu to g/mol just simply change the units FROM amu TO g/mol
“1” MOLE of any type of ATOM has a MASS in grams EQUAL TO the ATOM’s MASS measured in amu

16. C O EXAMPLE – Converting amu into C = 12.01 = 12 g/mol
O = = 16 g/mol
CO2 = 1 (C atom) (O atoms)
CO2 = 1 (12 g/mol) (16 g/mol)
CO2 = 12 g/mol g/mol
CO2 = 44 g/mol 6 C
carbon
12.01 8 O
oxygen
15.999

17. Avogadro’s Number: 6.02 x 1023 Amedeo Avogadro
Italian physicist (1811)
discovered that equal volumes of different gases contain equal numbers of molecules if pressure and temperature are kept constant
Avogadro’s number = 6.02 x 1023 particles/mole
Avogadro's number can be applied to any substance since it corresponds to the number of atoms/molecules needed to make up a mass equal to the substance's atomic or molecular mass in amu which then converts into g/mol

18. AVOGADRO’S NUMBER and MOLES:

19. HAPPY
MOLE
DAY
Oct 23rd