1. Chem Catalyst You have white, gray and black blocks. You rearrange the pieces on the left side to give the new combinations on the right side.+ 4g 3g5g ? How much does the gray block weigh? If you have 40 g of black blocks and 30 g of white-gray pieces, how many white-black pieces can you make? How did you solve the problem?

3. Part 2: The Big Mac 5. Assume that in order to make a Big Mac, you need two hamburger patties, 3 buns, 2 slices of cheese, and 1 slice of lettuce. Write a “chemical equation” for how to make a Big Mac. 2 Hamburger Patties + 3 Buns + 2 Cheese + 1 Lettuce  1 Big Mac

4. 6. Write out the ratios of bun to cheese, patties to burgers, etc. Write out as many as you can (there are at least 6).

5. 7. How many buns would you need in order to make 75 Big Macs? 75 BM x 3 buns = 225 buns 1 BM

6. 8.How many slices of cheese would you need to make 600 buns’ worth of Big Macs? 600 buns x 2 cheese= 400 cheeses 3 buns

7. 9.If you had 500 hamburger patties and 600 slices of cheese, how many Big Macs could you make? Which ingredient limits the number of burgers you can make? 600 cheese x 1 BM = 300 BM 2 cheese 500 patties x 1 BM= 250 BM 2 patties

8. Part 3: Using chemicals instead 1.Instead of making boxed lunches, a chemist wants to produce the compound calcium phosphate from the reaction between calcium chloride and sodium phosphate. 3CaCl 2 + 2Na 3 PO 4  Ca 3 (PO 4 ) 2 + 6 NaCl ***Coefficients are counting either molecules or moles of the chemical compound***

9. 3CaCl 2 + 2Na 3 PO 4  Ca 3 (PO 4 ) 2 + 6 NaCl 10. If you have 9 moles of CaCl 2, how many moles of calcium phosphate can you produce? Show your work. 9 mol CaCl 2 x 1 mol Ca 3 (PO 4 ) 2 = 3 mol Ca 3 (PO 4 ) 2 3 mol CaCl 2

10. 3CaCl 2 + 2Na 3 PO 4  Ca 3 (PO 4 ) 2 + 6 NaCl 11. How many moles of sodium phosphate would you need to make 10 moles of calcium phosphate? Show your work. 10 mol Ca 3 (PO 4 ) 2 x 2 mol Na 3 PO 4 = 20 mol Na 3 PO 4 1 mol Ca 3 (PO 4 ) 2

11. 3CaCl 2 + 2Na 3 PO 4  Ca 3 (PO 4 ) 2 + 6 NaCl 12.How many moles of sodium chloride would you make if 4 moles of sodium phosphate reacted with calcium chloride? 13.How many moles of sodium phosphate would be needed to react with 6 moles of calcium chloride? 4 mol Na 3 PO 4 x 6 mol NaCl = 12 NaCl 2 mol Na 3 PO 4 6 mol CaCl 2 x 2 mol Na 3 PO 4 = 4 mol Na 3 PO 4 3 mol CaCl 2

12. 14. How many moles of calcium chloride would you need to make 10 moles of calcium phosphate? 3CaCl 2 + 2Na 3 PO 4  Ca 3 (PO 4 ) 2 + 6 NaCl 10 mol Ca 3 (PO 4 ) 2 x 3 mol CaCl 2 = 30 mol CaCl 2 1 mol Ca 3 (PO 4 ) 2

13. 2NaCl  2Na + Cl 2 15. If 1 mole of sodium chloride decomposes, how many moles of sodium will you make? How many grams of sodium would you make? 1 mol NaCl x 2 mol Na = 1 mol Na 2 mol NaCl 1 mol Na = 22.99 g of Na

14. How many moles of chlorine gas are produced if 6 moles of sodium chloride decomposes? How many grams of chlorine gas would that be? 2NaCl  2Na + Cl 2 6 mol NaCl x 1 mol Cl 2 = 3 mol Cl 2 2 mol NaCl 3 mol Cl 2 x 70.9 g Cl 2 = 212.7 g Cl 2 1 mol Cl 2

15. Part 4: Moles and grams CaI 2 + Na 2 C 2 O 4  CaC 2 O 4 + 2NaI 17. Based on the balanced chemical equation, how many moles of sodium oxalate are needed to react with every one mole of calcium iodide? 1 mole

16. 18. Explain why the mass amount (in grams) of reactants calcium iodide and sodium oxalate is not equal, yet the mole amount is equal. CaI 2 Na 2 C 2 O 4 CaC 2 O 4 NaI Grams needed to make 128 g calcium oxalate 294 g134 g128 g298 g Moles needed to make 128 g calcium oxalate 1.0 moles 2.0 moles

17. Stoichiometry The part of chemistry that is concerned with the quantitative aspects of chemical reactions Deals with converting between masses and moles of reactants and products Mole Ratios: proportions in which two substances (reactants, or products, or both) combine or form

18. The “Mole Tunnel”

19. Grams of Known Grams of Unknown Moles of Unknown Moles of Known 1 2 3

20. Example Problem How many grams of NH 3 could you make from 75 grams of N 2 and an excess of H 2 gas?

21. Your turn: How many grams of NH 3 you could make from 12.8 grams of H 2 and an excess of N 2 gas?

22. Example problem: How many moles of H 2 would be necessary to fully react with 5.4 moles of N 2 ?

23. Your turn: How many moles of NH 3 would be produced from 22 moles of H 2 and an excess of N 2 ?

24. Example problem: How many moles of nitrogen gas are needed to react with 20 grams of hydrogen gas?

25. Your turn: How many moles of hydrogen gas are needed to react with 118 grams of nitrogen gas?