Name: __________________________________
Partner’s Name: ____________________________
Period: _____
What everyday recipes can teach us about chemistry?
Today we are considering the ratios and recipes you know and encounter all the time, but maybe don’t realize!
For example, have you thought about Oreos recently?
2 wafers + 1 creamy center  1 oreo
Part 1: Come up with three or more everyday “chemical reactions” like the one above. The amounts should be
whole numbers. They can have multiple products, as well!
1.
2.
3.
More:
Part 2: Choose your 3 favorite “reactions” from above. Label them a, b, & c and then use them below.
4. Choose 1 reactant and 1 product. What is the ratio of reactants to products?
(Example: 2 wafers to 1 oreo)
a.
b.
c.
5. Using the ratios from #4, predict the amount of reactant needed to produce 5 of your product.
(Example: 10 wafers needed to produce 5 oreos.)
a.
b.
c.
6. Using the ratios from #4, predict the amount of products you will get if you have 3 of your reactant.
(Example: 1.5 oreos will be produced from 3 wafers)
a.
b.
c.
Part 3: Consider the following reactions.
7. H2 + O2  H2O
a) Balance the chemical reaction: ___H2 +___ O2  ___ H2O
b) What is the ratio of [moles of oxygen used] to [moles of water produced]?
c) Predict the number of moles of H2 needed to produce 5 moles of water:
d) Predict the number of moles of water that will result from using 3 moles of O2 :
8. Ca + H2O  Ca(OH)2 + H2
a) Balance the chemical reaction: ___ Ca + ___ H2O  ___ Ca(OH)2 + ___ H2
b) What is the ratio of [moles of water used] to [moles of calcium hydroxide produced]?
c) Predict the number of moles of water needed to produce 5 moles of calcium hydroxide:
d) Predict the number of moles of calcium hydroxide that will result from using 3 moles of H2O:
9. Lithium sulfide + potassium phosphate  lithium phosphate + potassium sulfide
a) Write and balance the chemical reaction:
b) What is the ratio of [moles of lithium sulfide used] to [moles of potassium sulfide produced]?
c) Predict the number of moles of lithium sulfide needed to produce 5 moles of potassium sulfide:
d) Predict the number of moles of potassium sulfide that will result from using 3 moles of lithium sulfide:
10. potassium + chlorine  potassium chloride
a) Write and balance the chemical reaction:
b) What is the ratio of [moles of potassium used] to [moles of potassium chloride produced]?
c) Predict the number of moles of potassium needed to produce 5 moles of potassium chloride:
d) Predict the number of moles of potassium chloride that will result from using 3 moles of potassium:
11. copper (III) sulfate + barium  __barium sulfate__ + _________
a) Write and balance the chemical reaction:
b) What is the ratio of [moles of barium used] to [moles of barium sulfate produced]?
c) Predict the number of moles of barium needed to produce 5 moles of barium sulfate:
d) Predict the number of moles of barium sulfate that will result from using 3 moles of barium:
Part 4: Let’s consider how this relates to our airbag designs. The reaction in the lab was:
NaHCO3 + HC2H3O2 --> NaC2H3O2 + CO2 + H2O
12. What is the ratio of [moles of sodium bicarbonate used] to [moles of carbon dioxide produced]?
13. What is the ratio of [moles of acetic acid used] to [moles of carbon dioxide produced]?
14. If you had 2 moles of sodium bicarbonate, how many moles of carbon dioxide would be produced?
15. If you have 0.5 moles of acetic acid, how many moles of sodium bicarbonate do you think should be
used? (Give your best guess!)
Part 5: For all questions in this part, consider the following reaction from the Barking Dog Lab:
____ Al(s) + ___ HCl(aq)  ___ AlCl3(s) + ___ H2(g)
16. Balance the reaction above.
17. What is the ratio of [moles of aluminum used] to [moles of H2 produced]?
18. If 0.12 moles of HCl was used, how many moles of H2 can be produced?
19. If you used 10 grams of aluminum, how many moles of aluminum chloride can be produced?
(Hint: Figure out how many moles of aluminum you started with!)
Part 6: The reaction used to inflate airbags is shown below.
___ NaN3(s)  ___ Na(s) + ___ N2(g)
20. If 1 mole of sodium azide are used, how many moles of nitrogen gas (N2) are produced?
21. Your supervisor tells you that you need 3 moles of N2 to fully inflate your airbag. How many grams
of NaN3 are needed?