Lecture 10.2a- Mole Mass Conversions

Section 10.2 lecture (part A) for Honors & Prep Chemistry

1. Bellwork- An argument for recycling
An aluminum can contains 0.5 moles of
aluminum metal.
•How many particles are in the
aluminum can?
•How much does one mole of
aluminum weigh?
•What is the mass of the can?

2. Converting between
moles and number of particles
involves multiplying or dividing by
6.02 x 10
23

3. Converting between
moles and mass involves multiplying
or dividing by
the molar mass of the substance

4. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?

5. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles Mg

6. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles MgX

7. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles MgX
24.305 grams
1 mole Mg

8. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles MgX
24.305 grams
1 mole Mg
= 91.1 grams Mg

9. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles MgX
24.305 grams
1 mole Mg
= 91.1 grams Mg
WHERE THE
HECK DID THIS
COME FROM?!?

10. Convert from moles to mass
How much does 3.75 moles of
magnesium metal weigh?
3.75 moles MgX
24.305 grams
1 mole Mg
= 91.1 grams Mg
WHERE THE
HECK DID THIS
COME FROM?!?
Ü The periodic
table!

11. 10.5
Moles to grams
9.45 mol Al
2
O
3
x ___________ = 964g Al
2
O
3

1 mol Al
2
O
3
102g Al
2
O
3
2 Al = 54g
3 O = 48 g
102g

12. Grams to moles

16. Mole Review
huge #
of
particles
´ 6x10
23
¸ 6x10
23
(g)
grams
(mass)
molar
mass
molar
mass
¸
´
Use the
periodic
table!
Use the
mole
banner!

17. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of As

18. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms

19. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms

20. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms
= 4 moles As

21. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms
= 4 moles As

22. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms
= 4 moles As X
74.9 grams
1 mole

23. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of AsX
1 mole
6.02x10
23
atoms
= 4 moles As X
74.9 grams
1 mole

24. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of As
= 299.6 grams of Arsenic
X
1 mole
6.02x10
23
atoms
= 4 moles As X
74.9 grams
1 mole

25. Convert from number of
particles to mass in grams
2.4 x 10
24
atoms of As
= 299.6 grams of Arsenic ≈300g for multiple choice
X
1 mole
6.02x10
23
atoms
= 4 moles As X
74.9 grams
1 mole

26. 1. Calculate the mass in grams of a
sample containing 1.85 x 10
34
molecules
of water.
a. 3.07 x 10
10
g
b. 5.53 x 10
11
g
c. 188 g
d. 8.46 x 10
3
g
10.2 Section Quiz.

27. 2. Calculate the number of moles in a
spoonful of table sugar (C
12
H
22
O
11
)
having a mass of
10.5 g.
a. 32.6 mol
b. 3.59 ´ 10
3
mol
c. 3.07 ´ 10
–3
mol
d. 1.85 ´ 10
22
mol
10.2 Section Quiz.