1. Stoichiometry Chapter 11

3. Skills from Previous Chapters The following skills are not the only ones, but the main ones: Name to formula Balancing equations Molar conversions Conversion factors Molar mass

4. New Skills to be Learned  Determine mole to mole ratios  Stoichiometric calculations  Mole to mole  Mole to gram  Gram to gram  Determine limiting reactant

5. What is stoichiometry? The study of quantitative relationships between amounts of reactants used and amounts of products formed by a chemical reaction.

6. Mole to Mole Ratios First, we need an equation. Next we need to balance it.

7. Mole to Mole Ratios Once, the equation is balanced, identify the coefficients. These coefficients form the basis of the ratios.

8. Mole to Mole Ratios What is the ratio of hydrogen to nitrogen?

9. Problem 1 1.NaNO 3 + PbO  Pb(NO 3 ) 2 + Na 2 O What is the mole ratio of PbO to Na 2 O? What is the mole ratio of NaNO 3 to Pb(NO 3 ) 2 ?

10. Problem 2 1.AgI + Fe 2 (CO 3 ) 3  FeI 3 + Ag 2 CO 3 What is the mole ratio of AgI to FeI 3 ? What is the mole ratio of Ag 2 CO 3 ?

11. Problem 3 1.C 2 H 4 O 2 + O 2  CO 2 + H 2 O What is the mole ratio of C 2 H 4 O 2 to O 2 ? What is the mole ratio of O 2 to CO 2 ?

12. Problem 4 1.ZnSO 4 + Li 2 CO 3  ZnCO 3 + Li 2 SO 4 What is the mole ratio of ZnSO 4 to ZnCO 3 ? What is the mole ratio of Li 2 CO 3 to ZnCO 3 ?

13. Problem 5 1.V 2 O 5 + CaS  CaO + V 2 S 5 What is the mole ratio of CaS to V 2 S 5 ? What is the mole ratio of CaO to V 2 S 5 ?

14. Mole to Mole Problems Mole to mole ratios are key in determining the number of moles needed or produced of one element or compound, when given the moles of another.

15. Mole to Mole Problems First, an equation must be provided. – Either in word or skeletal form. If in words, you must change it into skeletal.

16. Mole to Mole Problems Second, the equation must be balanced.

17. Mole to Mole Problems Third, read the problem carefully. Identify what the problem is asking for. Example Problem: – In the aforementioned reaction, if 12 moles of hydrogen is reacted, how many moles of oxygen would be needed to complete the reaction? – What are they giving us? 12 moles of Hydrogen – What are they looking for? Moles of oxygen

18. Mole to Mole Problems Once, the given and wanted are established, we set up our problem. Since this is a mole to mole problem, only ONE conversion factor is needed.

19. Mole to Mole Problems In order to fill in the numbers, we must find the mole ratio of hydrogen to oxygen. Then we fill in the numbers.

20. Mole to Mole Problems Lastly, we calculate the answer.

21. Practice Problems C 2 H 4 O 2 + O 2  CO 2 + H 2 O If Bob is reacting 20 moles of oxygen, how many moles of carbon dioxide would he produce? If Sue produced 12.5 moles of water, how many moles of C 2 H 4 O 2 were used?

22. Practice Problems (2) AgI + Fe 2 (CO 3 ) 3  FeI 3 + Ag 2 CO 3 If.09 moles of Iron (III) iodide were produced, how many of silver (I) carbonate were produced? If 1.25 moles of iron (III) carbonate were used, how many of silver (I) iodide should have been?

23. Practice Problems (3) Al + O 2  Al 2 O 3 If 30 moles of aluminum are used, how many of aluminum oxide should be produced? If.05 moles of oxygen are used, how many of aluminum oxide should be produced?

24. Homework P. 372 – Practice Problems 3 and 4 P. 392 – #47 to 52 Study for Quiz on Mole to Mole problems

25. Mole to Gram Problems Going from moles to grams in an equation is based off of the ability to implement mole to mole problems. Within these mole to gram problems, two conversion factors will be used. – Mole to mole ratios – Molar mass

26. Mole to Gram Problems First, an equation must be provided. – Either in word or skeletal form. If in words, you must change it into skeletal.

27. Mole to Gram Problems Second, the equation must be balanced.

28. Mole to Gram Problems Third, read the problem carefully. Identify what the problem is asking for. Example Problem: – In the aforementioned reaction, if 12 moles of hydrogen is reacted, how many grams of oxygen would be needed to complete the reaction? – What are they giving us? 12 moles of Hydrogen – What are they looking for? Grams of oxygen

29. Mole to Gram Problems Once, the given and wanted are established, we set up our problem. Since this is a mole to gram problem, two conversion factors are needed.

30. Mole to Gram Problems In order to fill in the first conversion factor, we must find the mole ratio of hydrogen to oxygen. Then we fill in the numbers.

31. Mole to Gram Problems In order to fill in the second conversion factor, we must find the molar mass of O 2.

32. Mole to Gram Problems Once, the given and wanted are established, we set up our problem. Since this is a mole to gram problem, two conversion factors are needed.

33. Mole to Mole Problems Lastly, we calculate the answer.

34. Practice Problems C 2 H 4 O 2 + O 2  CO 2 + H 2 O If Bob is reacting 11 moles of oxygen, how many grams of carbon dioxide would he produce? If Sue produced 9 moles of water, how many grams of C 2 H 4 O 2 were used?

35. Practice Problems (2) AgI + Fe 2 (CO 3 ) 3  FeI 3 + Ag 2 CO 3 If 9 moles of Iron (III) iodide were produced, how many grams of silver (I) carbonate were produced? If 1.5 moles of iron (III) carbonate were used, how many grams of silver (I) iodide should have been?

36. Practice Problems (3) Al + O 2  Al 2 O 3 If 3 moles of aluminum are used, how many grams of aluminum oxide should be produced? If.5 moles of oxygen are used, how many grams of aluminum oxide should be produced?

37. Homework P. 376 – Practice problems # 13, 14 Study for quiz

38. Gram to Gram Problems Going from grams to grams in an equation is based off of the ability to implement mole to mole problems. Within these mole to gram problems, three conversion factors will be used. – Molar mass – Mole to mole ratios – Molar mass

39. Gram to Gram Problems First, an equation must be provided. – Either in word or skeletal form. If in words, you must change it into skeletal.

40. Gram to Gram Problems Second, the equation must be balanced.

41. Gram to Gram Problems Third, read the problem carefully. Identify what the problem is asking for. Example Problem: – In the aforementioned reaction, if 100g of hydrogen is reacted, how many grams of oxygen would be needed to complete the reaction? – What are they giving us? 100g of Hydrogen – What are they looking for? Grams of oxygen

42. Gram to Gram Problems Once, the given and wanted are established, we set up our problem. Since this is a mole to gram problem, three conversion factors are needed.

43. Gram to Gram Problems In order to fill in the first conversion factor, we must find the molar mass of hydrogen. Then we fill in the numbers.

44. Gram to Gram Problems In order to fill in the second conversion factor, we must find the mole ratio of hydrogen to oxygen.

45. Gram to Gram Problems To find the third conversion factor we must find the molar mass of oxygen.

46. Mole to Mole Problems Lastly, we calculate the answer.

47. Practice Problems C 2 H 4 O 2 + O 2  CO 2 + H 2 O If Bob is reacting 250 grams of oxygen, how many grams of carbon dioxide would he produce? If Sue produced 9 gramsof water, how many grams of C 2 H 4 O 2 were used?

48. Practice Problems (2) AgI + Fe 2 (CO 3 ) 3  FeI 3 + Ag 2 CO 3 If 10 grams of Iron (III) iodide were produced, how many grams of silver (I) carbonate were produced? If 150grams of iron (III) carbonate were used, how many grams of silver (I) iodide should have been?

49. Practice Problems (3) Al + O 2  Al 2 O 3 If 30 grams of aluminum are used, how many grams of aluminum oxide should be produced? If 500grams moles of oxygen are used, how many grams of aluminum oxide should be produced?

50. Homework P. 377 – Practice problems #15, 16 Study for quiz

51. Limiting Reactants

52. Limiting Reactant Involves Gram to Gram conversions

53. Example Problem The reaction between solid white phosphorus (P 4 ) and oxygen produces solid tetraphosphorus decoxide (P 4 O 10 ). Determine the mass of P 4 O 10 formed if 25g of P 4 and 50g of oxygen are combined. How much excess reactant remains after the reaction stops?

54. First Write the equation, and balance it.

55. Second Do gram to gram conversions for each of the reactants.

56. So… The limiting reactant is the one that produces the least amount! So, oxygen is the limiting reactant and 44.38g of P 4 O 10 are formed. Now, we must answer the second part of the question.

57. Third Now, we must find out how much of the excess reactant (P 4 ) is left over. So we must determine how much we use. To do this we must back convert from the product to P 4.

58. Fourth We subtract the used amount from the original amount, and find the excess.

59. Problems Handouts

60. Homework P. 394 – #76 to 82

61. End of Chapter Time for review packet.