Unit 8

1. Unit 8 Stoichiometry Chapter 12

2. Today… • Turn in: • Forensic Farming Reading • Fill Out Goal Sheet • Our Plan: • Begin Lab • Daily Challenge – Smore’s Stoichiometry • Notes – Stoichiometry Conversions • Worksheet #1 & Worksheet #2 • Wrap Up - Pyramid • Homework (Write in Planner): • WS#1 & WS#2 Due Monday

3. www.doh.state.fl.us

4. Lab Day 1 • Follow the procedure for Day 1 and begin recording observations • Use the internet to answer the Pre-Lab Questions

5. ChEck out the blue man!

6. Stoichiometry • Stoy-key-ahm-a-tree

7. What does it mean? • Comes from the combination of the Greek words stoikheioin, meaning “element”, and metron, meaning “to measure”

8. Definition • The study of the quantitative, or measurable, relationships in a chemical reaction.

9. Importance • Using stoichiometry, you can determine the quantities of reactants & products in a reaction from the BALANCED equation. • Like the Recipe!

10. Coefficients… • Doshow the number of moles of each substance involved in the rxn. • Do Notindicate the actual number of grams of the substance.

11. Example N2 + 3H2--> 2NH3 Atoms N Atoms H 2 6 On both the reactant and product side!

12. Example N2 + 3H2--> 2NH3 Molecule N2 Molecules H2 Molecules NH3 1 3 2

13. Example N2 + 3H2 --> 2NH3 1 Mole N2 Moles H2 Moles NH3 3 2

14. Example N2 + 3H2--> 2NH3 28 Grams N2 Grams H2 Grams NH3 6 34

15. Challenge • Which were conserved? • Atoms and Mass, but NOT Moles and Molecules!

16. Mole Ratio • A conversion factor that relates the amounts in moles of any 2 substances involved in a chemical reaction.

17. Molar Ratios from Last Example… N2 + 3H2--> 2NH3 3 moles H2 1 mole N2 2 moles NH3 3 moles H2 1 mole N2 2 moles NH3

18. Molecules Molecules 6.022 x 1023 6.022 x 1023 Mass Moles Given Molar Ratio Moles Unknown Mass Molar Mass Molar Mass PT Equation PT Volume 22.4 L/mole 22.4 L/mole Volume The Stoichiometry Map

19. Mole -->Mole Conversions • The conversion of moles of one type of substance to moles of another type of substance.

20. To Solve: Moles Given Molar Ratio Equation Moles Unknown

21. Example • H2 + I2--> 2HI • If 4 moles of H2 react, how many moles of HI will form?

22. Example H2 + I2--> 2HI 2 moles HI 4 moles H2 X = 8 moles HI 1 mole H2

23. Example 2 • If 0.8 moles of HI form, how many moles of I2 were used in the rxn?

24. Example 2 H2 + I2--> 2HI 1 mole I2 0.8 moles HI X = 0.4 moles I2 2 moles HI

25. Try it Out! 2H2 + O2--> 2H2O • If 1.3 moles of H2O form, how many moles of O2 were used in the rxn? (0.65 moles) • If 0.21 moles of H2 react, how many moles of H2O will form? (0.21 moles)

26. Mole -->Mass Conversions • Given the moles of one substance & asked to determine the mass of another substance.

27. To Solve: molar ratio equation molar mass PT Moles Given Mass Unknown Moles Unknown

28. Example C6H12O6 +6O2--> 6CO2 + 6H2O • What mass of sucrose was used if 3 moles of water formed?

29. Example C6H12O6 +6O2--> 6CO2 + 6H2O 1 mole C6H12O6 180g C6H12O6 3 moles H2O X X = 6 moles H2O 1 mole C6H12O6 90g C6H12O6

30. Example 2 • What mass of carbon dioxide was used to form 5.0 moles of water?

31. Example 2 C6H12O6 +6O2--> 6CO2 + 6H2O 6 moles CO2 5.0 moles H2O X 44g CO2 = X 1 mole CO2 6 moles H2O 220 g CO2

32. Try it Out! N2O5 + H2O -->2HNO3 • What mass of water was used to form 2.5 moles of HNO3? (23 g H2O) • What mass of HNO3 will form from 12.00 moles of N2O5? (1512 g HNO3)

33. Answer to #2 2 moles HNO3 63g. HNO3 12.00 moles N2O5 X X 1 mole N2O5 1 mole HNO3 = 1512 g. HNO3

34. Mass-->Mole Conversions • Given mass of one substance and asked to find moles of another substance.

35. To Solve molar mass PT molar ratio equation Moles Given Mass Given Moles Unknown

36. Example 2NO + 3H2--> 2NH3 + O2 • How many moles of NO were used to form 824g. NH3?

37. Example 2NO + 3H2--> 2NH3 + O2 1 mole NH3 2 moles NO 824g. NH3 X X 17g. NH3 2 moles NH3 48.5 moles NO =

38. Example How many moles of H2 were used to form 312 g of O2? 2NO + 3H2--> 2NH3 + O2 1 mole O2 3 moles H2 312g. O2 X X 32g. O2 1 mole O2 29.3 moles H2 =

39. Right Isosceles Scalene Obtuse Mole Safety Shower Pencil Cougars Chemistry Purple $300 $200 $50 $100 $250 $150 Acute Equilateral $100,000 Pyramid

40. Right Isosceles Scalene Obtuse Ratio Balance Stoichiometry Coefficient Molar Mass Periodic Table $300 $200 $50 $100 $250 $150 Acute Equilateral $100,000 Pyramid

41. Today… • Turn in: • Worksheet #1 & Worksheet #2 • Our Plan: • Conversions Table Review • Notes – Mass to Mass Conversions • Worksheet #3 • Homework (Write in Planner): • Worksheet #3 due next class

42. Molecules Molecules 6.022 x 1023 6.022 x 1023 Mass Moles Given Molar Ratio Moles Unknown Mass Molar Mass Molar Mass PT Equation PT Volume 22.4 L/mole 22.4 L/mole Volume The Stoichiometry Map

43. Team Conversion review • As a group of 3 or 4, complete the problems on the team conversion review. Each student should have a different colored writing utensil and you should take turns doing the work.

44. Molecules Molecules 6.022 x 1023 6.022 x 1023 Mass Moles Given Molar Ratio Moles Unknown Mass Molar Mass Molar Mass PT Equation PT Volume 22.4 L/mole 22.4 L/mole Volume The Stoichiometry Map

45. Mass-->Mass Conversions • Given the mass of one substance and asked to determine the mass of another substance.

46. To Solve: molar mass PT molar ratio equation molar mass PT Mass Given Moles Given Moles Unknown Mass Unkn

47. Example • 2Na + Cl2-->2NaCl • Find the mass of table salt produced from 18.6g Na.

48. Example 2Na + Cl2--> 2NaCl 1 mole Na 2 moles NaCl 58.5g NaCl 18.6g. Na X X X 23g. Na 2 mole Na 1 mole NaCl 47.3g NaCl =

49. Example • 2Al + Fe2O3--> Al2O3 + 2Fe • Find the mass of aluminum oxide produced from 2.3g of aluminum.

50. Example 1 mole Al 1 mole Al2O3 102g Al2O3 X 2.3g. Al X X 27g. Al 2 mole Al 1 mole Al2O3 = 4.3 g Al2O3 2Al + Fe2O3--> Al2O3 + 2Fe