1. How many picture frames can you make?
DIRECTIONS: Find your new lab group, get the bag assigned to your group, and determine
How many picture frames you can make given the supplies provided:
wooden splints = 1 side of the frame
aluminum foil = glass
hookeyes = hookeyes for stringing the wire on the back
wire = hanging wire
How many of each other type of supplies you will need to buy. See if you can use DIMENSIONAL ANALYSIS to do this!!
The “EQUATION” or recipe for making a picture frame.
Bring me your group’s answers on paper as soon as you are finished!! Then sit down at your desk.

2. If you have 36 pieces of wood, how many picture frames can you make?2

3. If you have 36 pieces of wood, how many picture frames can you make?
If you need 7 picture frames, how many pieces of glass do you need?

4. If you have 36 pieces of wood, how many picture frames can you make?
If you need 7 picture frames, how many pieces of glass do you need?
If you have 22 picture hanger hooks, how many picture frames can you make?

5. If you have 36 pieces of wood, how many picture frames can you make?
If you need 7 picture frames, how many pieces of glass do you need?
If you have 22 picture hanger hooks, how many picture frames can you make?
If you have 9 pieces of wire, how many picture frames can you make?

6. You’ve just done your first Stoichiometry problems!!
If you have 36 pieces of wood, how many picture frames can you make?
If you need 7 picture frames, how many pieces of glass do you need?
If you have 22 picture hanger hooks, how many picture frames can you make?
If you have 9 pieces of wire, how many picture frames can you make?
Guess What??
You’ve just done your first
Stoichiometry problems!!

7. You’ve just done your first Stoichiometry problems!!
If you have 36 pieces of wood, how many picture frames can you make?
If you need 7 picture frames, how many pieces of glass do you need?
If you have 22 picture hanger hooks, how many picture frames can you make?
If you have 9 pieces of wire, how many picture frames can you make?
Guess What??
You’ve just done your first
Stoichiometry problems!!
4 wood pieces + 1 piece of glass + 2 hooks + 1 wire = 1 frame!

8. Stoichiometry Why is it important?

9. Stoichiometry What would happen if too much or not enough “air” was produced during a crash?

10. Picture Frames and Chemistry…Huh!?!?
Just like picture frames are composed of parts in certain ratios, chemists have ratios as well
Chemists call them reaction equations
Furthermore, we use moles to count what we need
Lastly, instead of wood, glass, wire, and hooks, we use chemical compounds as sodium azide, or oxygen and hydrogen!

11. Picture Frames and Chemistry…Huh!?!?
4 wood pieces + 1 piece of glass + 2 hooks + 1 wire = 1 frame!
Not too different from
____ NaN3(s) ---> ____ Na3N(s) + ____ N2(g)
Sodium azide ---> sodium nitride + nitrogen gas.
Balanced equations are essential, so let’s do it!

12. Picture Frames and Chemistry…Huh!?!?
4 wood pieces + 1 piece of glass + 2 hooks + 1 wire = 1 frame!
Not too different from
___ NaN3(s) ---> ____ Na3N(s) + ____ N2(g)
1 - Na - 3
3 - N - 3
Sodium azide ---> sodium nitride + nitrogen gas.

13. Picture Frames and Chemistry…Huh!?!?
4 wood pieces + 1 piece of glass + 2 hooks + 1 wire = 1 frame!
Not too different from
__3_ NaN3(s) ---> _1__ Na3N(s) + __4_ N2(g)
3 1 - Na - 3 N
Sodium azide ---> sodium nitride + nitrogen gas

14. Mole Ratios
These mole ratios can be used to calculate the moles of one chemical from the given amount of a different chemical
Example: How many moles of sodium azide are needed to produce 5 moles of nitrogen gas?
3 NaN3(s) ---> 1 Na3N(s) N2(g)
5 moles N2 3 mol NaN3
4 mol N2
= 3.75 moles NaN3

15. Mole-Mole Conversions
3 NaN3(s) ---> 1 Na3N(s) N2(g)
Sodium azide ---> sodium nitride + nitrogen gas
How many moles of sodium azide do you need to produce 2.6 moles of nitrogen?
How many moles of sodium nitride will be produced if 2.6 moles of nitrogen are produced?

16. Mole-Mole Conversions
3 NaN3(s) ---> 1 Na3N(s) N2(g)
Sodium azide ---> sodium nitride + nitrogen gas
How many moles of sodium azide do you need to produce 2.6 moles of nitrogen?
2.6 moles N2 3 moles NaN3 = 1.95 moles
4 moles N2 NaN3

17. Mole-Mole Conversions
3 NaN3(s) ---> 1 Na3N(s) N2(g)
Sodium azide ---> sodium nitride + nitrogen gas
How many moles of sodium nitride will be produced if 2.6 moles of nitrogen are produced?
2.6 moles N2 1 moles Na3N = 0.65 moles
4 moles N2 Na3N

18. htYouTube
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Practice
Write the balanced reaction for hydrogen gas reacting with oxygen gas.
__ H2 + ___ O2  ___ H2O

19.
Practice
Write the balanced reaction for hydrogen gas reacting with oxygen gas.
2 H2 + O2  2 H2O Right?

20.
Practice
Write the balanced reaction for hydrogen gas reacting with oxygen gas.
2 H2 + O2  2 H2O
How many moles of reactants are needed?
What if we wanted 4 moles of water?

21.
Practice
Write the balanced reaction for hydrogen gas reacting with oxygen gas.
2 H2 + O2  2 H2O
How many moles of reactants are needed?
What if we wanted 4 moles of water?
What if we had 3 moles of oxygen, how much hydrogen would we need to react, and how much water would we get?

22. Mole-Mass Conversions
Most of the time in chemistry, the amounts are given in grams instead of moles
We still go through moles and use the mole ratio, but now we also use molar mass to get to grams
Example: How many grams of chlorine are required to react completely with 5.00 moles of sodium to produce sodium chloride?
2 Na + Cl2  2 NaCl
5.00 moles Na 1 mol Cl g Cl2
2 mol Na 1 mol Cl2
= 177g Cl2

23. Practice
Calculate the mass in grams of Iodine required to react completely with 0.50 moles of aluminum.

24. Mass-Mole
We can also start with mass and convert to moles of product or another reactant
We use molar mass and the mole ratio to get to moles of the compound of interest
Calculate the number of moles of ethane (C2H6) needed to produce 10.0 g of water
2 C2H6 + 7 O2  4 CO2 + 6 H20
10.0 g H2O 1 mol H2O 2 mol C2H6
18.0 g H2O 6 mol H20
= mol C2H6

25. Practice
Calculate how many moles of oxygen are required to make 10.0 g of aluminum oxide

26. Chemistry
Looking at a reaction tells us how much of something you need to react with something else to get a product. Be sure you have a balanced reaction before you start!
Example: 2 Na + Cl2  2 NaCl
This reaction tells us that by mixing 2 moles of sodium with 1 mole of chlorine we will get 2 moles of sodium chloride
What if we wanted 4 moles of NaCl? 10 moles? 50 moles?

27. Mass-Mass Conversions
Most often we are given a starting mass and want to find out the mass of a product we will get (called theoretical yield) or how much of another reactant we need to completely react with it (no leftover ingredients!)

28. Everything must go through Moles!!!
Calculations
Known Unknown
Substance A Substance B
Mass
Mole

29. Mass-Mass Conversion
Ex. Calculate how many grams of ammonia are produced when you react 2.00g of nitrogen with excess hydrogen.
N2 + 3 H2  2 NH3
2.00g N mol N mol NH g NH3
28.02g N2 1 mol N mol NH3
= 2.4 g NH3

30. Practice
How many grams of calcium nitride are produced when 2.00 g of calcium reacts with an excess of nitrogen?

31. never knew his own number; it was named in his honor by a
Amedeo Avogadro ( )
never knew his own number;
it was named in his honor by a
French scientist in 1909.
its value was first estimated
by Josef Loschmidt, an Austrian
chemistry teacher, in 1895.

32. How long would it take a computer that can count 10,000,000 atoms per second to count a mole of atoms?
A mole of marbles would cover the Earth, including
The ocean how deeply?
A mole of $100 bills stacked on top of each other would reach how far out in the solar system? (Careful, this may be a trick question!)

33. How Big is a Mole? One mole of marbles would cover the entire Earth
A: A computer that can count 10,000,000 atoms per second would
take 2,000,000,000 years to count 1 mole of a substance.
How Big is a Mole?
One mole of marbles would cover the entire Earth
(oceans included) for a depth of three miles.
One mole of $100 bills stacked one on top of another
would reach from the Sun to Pluto and back 7.5 million
times.

34. How Big is a Mole?
One mole of $100 bills stacked one on top of another
would reach from the Sun to Pluto and back 7.5 million
times.
How many light years (yes, light years!!) would it take light to travel the height of this stack of $100 dollar bills?

35. It would take light 9500 years to travel from the
Q: Can you give me an example to put that number in perspective?
A: A computer that can count 10,000,000 atoms per second would
take 2,000,000,000 years to count 1 mole of a substance.
It would take light 9500 years to travel from the
bottom to the top of a stack of 1 mole of $1 bills.