1. Ch10.1 – The Mole
1 mol = 6.02 x 1023 particles
This is called Avogadro’s Number
*Think of it as a chemist’s dozen
(A dozen donuts or a mole of donuts?)
Can be used for atoms, ions, molecules, donuts, oranges,
grains of sand, chevys, etc.
Why that number?
-Since 1 amu = 1.66 x 10-24g:
= 1 x

2. The Mole
Can use as a unit for counting numbers
Atoms are too small to count individually and there are too many, so we need a way to bundle a bunch, like having a dozen oranges = 12 oranges
1 mole = 6.02 x 1023 particles
This is hard to understand, so let’s relate it.
Did You Know???
A grain of rice has an average mass of 1.75 x 10-5kg. What is the mass of one mole, 6.02 x 1023, grains of rice? x 1019 kilograms This is hard to understand, so let’s change this mass to the mass of cars. This would require a million cars per person to equal this mass!!
You can count the number of oranges in 6 dozen in a few minutes. Six moles of oranges would have a mass as large as the entire Earth!
Avogadro’s number (1 mole) is so large, if you could count 100 particles every minute and counted 12 hrs every day, and had every person on Earth also counting, it would take more than 4 million years to count a mole of anything!
To obtain Avogadro’s number in grains of sand, it would be necessary to dig up the entire surface of the Sahara Desert, an area of 8 x 106km2 (an area slightly less than the area of the U.S.), to a depth of 200m.

3. Conversions: or
6.02 x 1023 particles
1 mol
Ex 1) How many moles of Mg are 3.01 x 1022 atoms?
Ex 2) How many molecules are 4.00 mol of glucose, C6H12O6?
HW #2) How many atoms are 0.360mol of Silver?

4. Gram Formula Mass
Ex3) He weighs or
C weighs or
The mole # was chosen so that the # on the Periodic Table
can be read in grams.
*Round masses to nearest 1/10*
Ex4)H F Cl

5. Ex5) Find the molecular mass of:
H2O
NaCl
Mg3 (PO4)2
Ch 10 HW #1 1 – 7

6. Ch10 HW#1 1 – 7
1) How many moles in 2.80 x 1024 atoms of silicon?
3) How many oxygen atoms in each: A) NH4NO3 B) C9H8O4 C) O3 D) C3H5(NO3)3

7. Ch10 HW#1 1 – 7
1) How many moles in 2.80 x 1024 atoms of silicon?
2) (In class)
3) How many oxygen atoms in each: A) NH4NO3 B) C9H8O4 C) O3 D) C3H5(NO3)3
1 moles
2.80 x 1024 atoms
= 4.65 moles
6.02 x 1025 atoms

8. Ch10 HW#1 1 – 7
1) How many moles in 2.80 x 1024 atoms of silicon?
2) (In class)
3) How many oxygen atoms in each: A) NH4NO3 3 B) C9H8O4 4 C) O3 3 D) C3H5(NO3)3 9
1 moles
2.80 x 1024 atoms
= 4.65 moles
6.02 x 1025 atoms

9. 4) How many molecules in 2.14 mol CO?
5) How many moles in 4.65 x 1024 molecules of NO2?

10. 4) How many molecules in 2.14 mol CO?
5) How many moles in 4.65 x 1024 molecules of NO2?
6.02 x 1023 molecules
2.14 mol CO
= 1.29 x molecules
1 mol CO

11. 4) How many molecules in 2.14 mol CO?
5) How many moles in 4.65 x 1024 molecules of NO2?
6.02 x 1023 molecules
2.14 mol CO
= 1.29 x molecules
1 mol CO
4.63 x 1024 molecules
1 moles
= 7.72 moles
6.02 x 1023 molecules

12. 6) Gram molecular mass
A. C2H B. PCl3
C. C3H7OH D. N2O5

13. 6) Gram molecular mass
A. C2H B. PCl3
C. C3H7OH D. N2O5 =
= 24.0
= 106.5
= 6.0
137.5 g/mol
30.0 g/mol

14. 6) Gram molecular mass
A. C2H B. PCl3
C. C3H7OH D. N2O5 =
= 24.0
= 106.5
= 6.0
137.5 g/mol
30.0 g/mol
= 28.0
= 36.0
= 80.0
8 1.0 =
= 16.0
108.0 g/mol
60.0 g/mol

15. 7) Gram Formula Mass
A. Sr(CN)2 B. NaHCO3
C. Al2(SO3)3

16. 7) Gram Formula Mass
A. Sr(CN)2 B. NaHCO3
C. Al2(SO3)3
= 87.6
= 24.0
= 28.0
139.6 g/mol

17. 7) Gram Formula Mass
A. Sr(CN)2 B. NaHCO3
C. Al2(SO3)3
= 87.6
= 23.0
= 24.0
1 1.0 =
= 28.0 = =
139.6 g/mol
83.8 g/mol

18. 7) Gram Formula Mass
A. Sr(CN)2 B. NaHCO3
C. Al2(SO3)3
= 87.6
= 23.0
= 24.0
1 1.0 =
= 28.0 = =
139.6 g/mol
83.8 g/mol
= 54.0 =
= 144.0
294.3 g/mol

19. Ch10.2 – Mole/Mass Conversions
Ex 1) How many grams are in 7.20 mol of dinitrogen trioxide?
Ex 2) How many grams are in 3.41 mol of calcium oxide?
Ex 3) Find the number of moles in 92.81g of Iron (III) Oxide?

20. Ch10.2 – Mole/Mass Conversions
Ex 1) How many grams are in 7.20 mol of dinitrogen trioxide?
Ex 2) How many grams are in 3.41 mol of calcium oxide?
7.20 mol N2O3
76.0 grams N2O3
= 547 grams N2O3
1 mol N2O3
= 28.0
= 48.0
76.0 g/mol
= 191 grams CaO
Ex 3) Find the number of moles in 92.81g of Iron (III) Oxide?
= .581 Moles

21. HW#8) Find the mass of each:
0.720 mol Be
b) mol N2
(finish c, d)
HW#9) Find # of moles in each:
b) g Li2HPO4
(finish #9)
Ch 10 HW#2 8, 9

22. Ch3 X.C.
Average Density of Earth.
Given: DiameterE = 12,756 km
MassE = 5.98x1024 kg
VolumeΘ = 4/3 πr3
DiameterE km
VolumeE = 4/3.πr3 = 4/3.π(637,800,000 cm)3 = 1.09x1027 cm3
MassE = 5.98 x 1024 kg x g
m x 1027g
V x 1027 cm3
RadiusE = = = km = 637,800,000 cm
D= = = 5.50 g/cm3

23. Ch10 HW#2 8 – 9
8c) Convert to mass:
10.0 mol Cr
d) mol K

24. Ch10 HW#2 8 – 9
8c) Convert to mass:
10.0 mol Cr g Cr
1 mol Cr = 520g Cr
d) mol K g K
1 mol K = 130 g K

25. Ch10 HW#2 8 – 9
8c) Convert to mass:
10.0 mol Cr g Cr
1 mol Cr = 520g Cr
d) mol K g K
1 mol K = 130 g K
9) Find moles
a) 5.00g H2
c) 72.0g Ar
d) 3.70x10 -1 g

26. Ch10 HW#2 8 – 9
8c) Convert to mass:
10.0 mol Cr g Cr
1 mol Cr = 520g Cr
d) mol K g K
1 mol K = 130 g K
9) Find moles
a) 5.00g H2 1 mol H2
2.0 g H2 = 2.5 mol H2
c) 72.0g Ar 1 mol Ar
39.9g Ar = 1.80 mol Ar
d) 3.70x10 -1 g 1 mol B
10.8g B =

27. Ch10.3 – Using the Mole
Ex) What is the mass of 3.01x1023 atoms of Carbon?
Ex) What is the mass of 12.04x1023 molecules of oxygen?
Ex) How many molecules are there in 63.8g of ethanol, CH3OH?
Ch10 HW #3 (10-12)

28. Ch10.3 – Using the Mole
Ex) What is the mass of 3.01x1023 atoms of Carbon?
3.01x1023 atoms C 1 mol C g C
6.02x1023 atoms C 1 mol C = 6.00g C
Ex) What is the mass of 12.04x1023 molecules of oxygen?
12.04x1023 molecules O mol O g O2
6.02x1023 molec. O2 1 mol O2 = 64.0g O2
Ex) How many molecules are there in 63.8g of ethanol, CH3OH?
63.8g CH3OH 1 mol CH3OH 6.02 x 1023 molecules CH3OH
32.0g CH3OH mol CH3OH
= 1.20 x 1024 molecules CH3OH
Ch10 HW #3 (10-12)

29. Lab10.1 – Molar Mass
- due tomorrow
- Ch10 HW#3 due at beginning of period

30. Ch10 HW #3 10 – 12
10) What is the mass of 2.11 x 1024 molecules of sulfur dioxide?
2.11 x 1024 molecules SO2
= 32.1
2 16 =
64.1 g/mol

31. 10) What is the mass of 2.11 x 1024 molecules of sulfur dioxide?
2.11 x 1024 molecules SO2
1 moles SO2
64.1g SO2
= 224g SO2
6.02 x 1023
molecules SO2
1 moles SO2
= 32.1
2 16 =
64.1 g/mol

32. 11) What is the mass of 1.0 x 1022 molecules of iodine?
1.0 x 1022 molecules I2
= g/mol

33. 11) What is the mass of 1.0 x 1022 molecules of iodine?
1.0 x 1022 molecules I2
1 moles I2
253.8g I2
= 4.22g I2
6.02 x 1023
molecules I2
1 moles I2
= g/mol

34. 12) How many molecules is 126.7g of sucrose?
126.7g C6H12O6
= 72.0
= 12.0
= 96.0
180.0 g/mol

35. 12) How many molecules is 126.7g of sucrose?
6.02 x 1023
molecules C6H12O6
126.7g C6H12O6
1 mol C6H12O6
180.0g C6H12O6
1 mol C6H12O6
= 4.23 x 1023
molecules C6H12O6
= 72.0
= 12.0
= 96.0
180.0 g/mol

36. Ch10.4 – Volume of a Mole of Gas
Volumes of gases can change a lot, if temp or pressure change.
Standard temperature and pressure: (STP)
Temp: 0°C (273K)
Pressure: kPa (kiloPascals) or 1 atmosphere
At STP, 1 mole of any gas occupies a volume of 22.4 Liters.
22.4 L
1 mol
1 mol
22.4 L or

37. Ch10.4 – Volume of a Mole of Gas
Volumes of gases can change a lot, if temp or pressure change.
Standard temperature and pressure: (STP)
Temp: 0°C (273K)
Pressure: kPa (kiloPascals) or 1 atmosphere
At STP, 1 mole of any gas occupies a volume of 22.4 Liters.
Ex 1) What is the volume of mol of SO2 gas at STP?
22.4 L
1 mol
1 mol
22.4 L or

38. Ch10.4 – Volume of a Mole of Gas
Volumes of gases can change a lot, if temp or pressure change.
Standard temperature and pressure: (STP)
Temp: 0°C (273K)
Pressure: kPa (kiloPascals) or 1 atmosphere
At STP, 1 mole of any gas occupies a volume of 22.4 Liters.
Ex 1) What is the volume of mol of SO2 gas at STP?
22.4 L
1 mol
1 mol
22.4 L or
0.600 mol SO2
22.4 L SO2
= 13.4 L SO2
1 mol SO2

39. Ex 2) Determine the # of moles in 33.6 L of He gas at STP:
Ex 3) The density of a gaseous compound of C and O is g/L
at STP. Determine the gram formula mass. Is it CO or CO2?
CO: = 12.0
= 16.0
20.0 g/mol
CO2: = 12.0
= 32.0
44.0 g/mol

40. Ex 2) Determine the # of moles in 33.6 L of He gas at STP:
Ex 3) The density of a gaseous compound of C and O is g/L
at STP. Determine the gram formula mass. Is it CO or CO2?
1.964g
1 L
1 mol He
= 1.50 mol He
22.4 L He
CO: = 12.0
= 16.0
20.0 g/mol
CO2: = 12.0
= 32.0
44.0 g/mol

41. Ex 2) Determine the # of moles in 33.6 L of He gas at STP:
Ex 3) The density of a gaseous compound of C and O is g/L
at STP. Determine the gram formula mass. Is it CO or CO2?
1.964g
1 L
1 mol He
= 1.50 mol He
22.4 L He
1.964g
1 L
22.4 L
= 44.0 g/mol
1 mol
CO: = 12.0
= 16.0
20.0 g/mol
CO2: = 12.0
= 32.0
44.0 g/mol

42. Ex4) 10.4g of dry ice, CO2 , is allowed to sublime into a gas.
If the gas is brought to STP, what volume does it occupy?
Ex5) 1.13x1022 molecules of hydrogen gas occupy what volume
at STP?

43. Ex4) 10.4g of dry ice, CO2 , is allowed to sublime into a gas.
If the gas is brought to STP, what volume does it occupy?
= 5.29L CO2
10.4g CO2
1 mol CO2
22.4L CO2
44.0g CO2
Ex5) 1.13x1022 molecules of hydrogen gas occupy what volume
at STP?

44. Ex4) 10.4g of dry ice, CO2 , is allowed to sublime into a gas.
If the gas is brought to STP, what volume does it occupy?
= 5.29L CO2
10.4g CO2
1 mol CO2
22.4L CO2
44.0g CO2
Ex5) 1.13x1022 molecules of hydrogen gas occupy what volume
at STP?
= .420L H2
1.13x1022 molecules H2
1 mol H2
22.4L H2
6.02x1023 molecules H2
Ch 10 HW #

45. Ch 10 HW#4 13-18 ( XC for correct #16 )
13) 3 balloons each contain the same # of molecules of 3 different STP.
Same mass? Same volume?
CO2 O2 H2

46. Ch 10 HW#4 13-18 ( XC for correct #16 )
13) 3 balloons each contain the same # of molecules of 3 different STP.
Same mass? Same volume?
Diff mass
Same volume
CO2 O2 H2

47. 14) STP
a) 3.20x10-3 mol CO2
b) mol CH4
c) 3.70 mol N2
15) At STP, how many moles?
a) 67.2L SO2
b) 0.880L He
c) 1.00x103L C2H6

48. 14) STP
a) 3.20x10-3 mol CO L CO2
1 mol CO2 = .0717l CO2
b) mol CH L CH4
1 mol CH4 = 21.5L CH4
c) 3.70 mol N L N2
1 mol N2 = 82.9L N2
15) At STP, how many moles?
a) 67.2L SO mol SO2
22.4 L SO2 =
b) 0.880L He 1 mol He
22.4 L He =
c) 1.00x103L C2H6 1 mol C2H6
22.4 L C2H6 =

49. 14) STP
a) 3.20x10-3 mol CO L CO2
1 mol CO2 = .0717l CO2
b) mol CH L CH4
1 mol CH4 = 21.5L CH4
c) 3.70 mol N L N2
1 mol N2 = 82.9L N2
15) At STP, how many moles?
a) 67.2L SO mol SO2
22.4 L SO2 = 3.00 mol SO2
b) 0.880L He 1 mol He
22.4 L He = mol He
c) 1.00x103L C2H6 1 mol C2H6
22.4 L C2H6 = 44.6 mol C2H6

50. 16) AT STP what volume does 12.2g fluorine gas occupy?
12.2 g F2 1 mol F L F2
38.0 g F mol F2 =
17) 13.0 x 1024 molecules of Argon occupy what volume at STP?
13.0 x 1024
molecules Ar 1 mol Ar L Ar
6.02 x mol Ar =
molecules Ar

51. 16) AT STP what volume does 12.2g fluorine gas occupy?
12.2 g F2 1 mol F L F2
38.0 g F mol F2 = 7.19 L F2
17) 13.0 x 1024 molecules of Argon occupy what volume at STP?
13.0 x 1024
molecules Ar 1 mol Ar L Ar
6.02 x mol Ar =
molecules Ar

52. 16) AT STP what volume does 12.2g fluorine gas occupy?
12.2 g F2 1 mol F L F2
38.0 g F mol F2 = 7.19 L F2
17) 13.0 x 1024 molecules of Argon occupy what volume at STP?
13.0 x 1024
molecules Ar 1 mol Ar L Ar
6.02 x mol Ar = 484 L Ar
molecules Ar

53. 18) The densities of 3 gases:
A: 1.25 g/L B: 2.86 g/L
C:0.714 g/L
Calculate the gFm of each (g/mol)
ID as NH3, SO2, Cl2, N2, or CH4
1.25 g L
1 L mol =
B) g L
C) g L
NH3: 14.0 = 14.0
1.0 = 3.0
17.0 g/mol
SO2: = 32.1
= 32.0
64.1 g/mol
Cl2: = g/mol
N2: = g/mol
CH4: = 12.0
4 1.0 = 4.0
16.0 g/mol

54. 18) The densities of 3 gases:
A: 1.25 g/L B: 2.86 g/L
C:0.714 g/L
Calculate the gFm of each (g/mol)
ID as NH3, SO2, Cl2, N2, or CH4
1.25 g L
1 L mol = 28.0 g/mol
B) g L
1 L mol = 64.1 g/mol
C) g L
1 L mol = 16.0 g/mol
NH3: 14.0 = 14.0
1.0 = 3.0
17.0 g/mol
SO2: = 32.1
= 32.0
64.1 g/mol
Cl2: = g/mol
N2: = g/mol
CH4: = 12.0
4 1.0 = 4.0
16.0 g/mol

55. Ch10.5 – More Conversions
Ex1) One copper cylinder from the last lab had a mass of 57.68g.
How many copper atoms is that?
Ex2) Dinitrogen monoxide is stored in a 2.00 L cylinder at STP.
What mass is this?

56. Ch10.5 – More Conversions
Ex1) One copper cylinder from the last lab had a mass of 57.68g.
How many copper atoms is that?
57.68g Cu 1 moles Cu x1023 atoms
63.5g Cu moles Cu = 5.47x1023 atoms Cu
Ex2) Dinitrogen monoxide is stored in a 2.00 L cylinder at STP.
What mass is this?
2.00 L N2O 1 moles N2O g N2O
22.4 L N2O moles N2O = 3.93 g N2O

57. Ex3) Hydrogen sulfide is a dangerous gas released in volcanoes.
If a scientist collects 10.0 mL sample at STP,
how many gas particles are present?

58. Ex3) Hydrogen sulfide is a dangerous gas released in volcanoes.
If a scientist collects 10.0 mL sample at STP,
how many gas particles are present?
.0100L H2S 1 mole H2S 6.02x1023 particles H2S
22.4 L H2S moles H2S = 2.69x1020 particles
Ch10 HW#4 Mid Ch Rev Problems

59. Lab9.1 – Formulas and Oxidation Numbers Review
- due 2 days
- Mid Ch Rev due at beginning of period

60. Ch10 Mid Chapter Review
How many atoms are in 1.23 moles of calcium?
How many grams are in 1.23 moles of calcium?
How many moles of carbon are in 5.5 g sample of carbon?

61. 4. How many moles of aluminum are there in 2.3x1024 atoms?
5. How many liters are in 2.50 moles of hydrogen molecules, H2?

62. 6. How many moles are in 3.04 liters of chlorine gas?
7. How many particles are in 55.6 g of calcium oxide?
8. How many liters of gas are produced when 10.3 g of dry ice,
solid carbon dioxide, sublimes?

63. Ch10 Review
How many moles in 1.50x1023 molecules NH3?
2) Calculate the gram formula mass of H3PO4. 3 1 4
3) How many moles in 15.5 g SiO2?

64. Ch10 Review
How many moles in 1.50x1023 molecules NH3?
1.50x1023 molecules NH3 1 mol NH3
6.02x1023 molecules NH3 =.249 moles NH3
2) Calculate the gram formula mass of H3PO4. =
= = 98.0 g/mol
= 64.0
3) How many moles in 15.5 g SiO2?

65. 3) How many moles in 15.5 g SiO2?
4) Find the mass of 1.50 moles C5H12

66. 3) How many moles in 15.5 g SiO2?
15.5 g SiO mol SiO2
60.1 g SiO2 = .257 mol SiO2
4) Find the mass of 1.50 moles C5H12
1.50 moles C5H g C5H12
1 mol C5H12 = 108 g C5H12

67. 5) Calculate the volume of 7.6 mole Ar at STP.
6) Find the volume of 835 g SO3 at STP.

68. 5) Calculate the volume of 7.6 mole Ar at STP.
7.6 mol Ar L Ar
1 mol Ar = 170 L Ar
6) Find the volume of 835 g SO3 at STP.
835g SO mol SO L SO3
80.1 g SO mol SO3 = 234 L SO3

69. Chapter 10 Hw #4 19 – 22
19) Mass in grams of an atom of Hg?
1 atom Hg mol Hg g Hg
6.02x1023 atoms Hg 1 mol Hg = 3.33x10-22 g
20) How many molecules are in a 4.00 L balloon (at STP) filled with carbon dioxide?
Would the answer change if CO?
9.00L CO2 1mol CO x1023 molecules
22.4 L CO2 1 mol CO2 = 2.42x1023 molecules
21) % comp
9.03g Mg with 3.48g N
9.03g Mg g N
12.51g total x100% = 72% g total x100% = 28%
B) 29.0g Ag with 4.30g S
29.0g Ag g S
33.30g total x100% = 87% g total x100% = 13%

70. 22) % comp of ethane C2H6
(assume 1 mol) = 24.0
= 6.0
30.0 g/mol
C: 24.0g C H: 6.0g H
30.0g total x100% = 80% g total x100% = 20%

71. Molarity
Molarity – a measure of concentration, represented with the symbol (M)
- defined as Molarity (M) = Moles of Solute/Liter of solution
- solute the substance added to the solution
Ex: NaCl added to pure water to make a salt water solution.
solute solvent
- sometimes the solution is measured in dm3 instead
1L = 1 dm3
Ex) What is the molarity of a solution made by dissolving 45.2g of Ca(OH)2 in
250 mL of solution?
45.2 Ca(OH)2 1 mol Ca(OH)2
74.0g Ca(OH)2 = .611 mL Ca(OH)2
= 40.1
= KHDUdcm .611mL
2 1.0 = mL = .250 L .250 L =2.44 M Ca(OH)2
74.0 g/mol

72. Ex) What is the molarity of a solution made by dissolving 10g of potassium chloride in
0.505 dm3 of solution?
10g KCl mol KCl
74.6g KCl = .134 mol KCl = .265 M KCl
.505 L
= 39.1
= 35.5
74.6