Topics for Today

1. Topics for Today • From Fats to Soap!

2. Topics for Today • What is a soap? • Why do soaps clean? • What is dirt? • What is hard water? • How do we make a soap?

3. Readings for Today • Section 5.12.1 – How Hard is Your Water?

4. Topics for Wednesday • From Soap to Biodiesel!!

5. Topics for Wednesday • Why biodiesel? • How are soap and biodiesel different? No text readings

6. Topics for Friday EXAM 4!!!!

7. Announcements! HW 5 due Thursday the 10th!

8. Final Exam!! Friday, May 18th

9. Only if you have 3 finals within 24 hours of each other Final Exam!! Can I take it early? Chancellor John Wiley

10. Topics for Today • From Fats to Soap!

11. Generic term for the soluble salt of a fatty acid What is a soap?

12. Generic term for the soluble salt of a fatty acid What is a soap?

13. Review What is a salt? The product of an acid-base reaction!

14. Neutralization Reaction Acid + Base Salt + Water  NaNO3 + HOH HNO3 + NaOH H+ NO3- Na+ OH- Na+ NO3- H+ OH- Can you use carboxylic acids? There WILL be a neutralization reaction (in some fashion) on Exam #4!!

15. Carboxylic Acids Ethanoic/Acetic Acid (Vinegar) Where does the H+ come from? O CH3 C OH CH3COO- (Acetate ion) H+

16. Neutralization Reaction- Review Acid + Base Salt + Water Acetic Acid + NaOH Sodium Acetate + H2O O O + + H2O NaOH CH3 C CH3 C O- Na+ OH

17. Soap • Generic term for the soluble salt of a fatty acid

18. Review What is a fatty acid?

19. Three Triple H+ Fatty Acids + Alcohol Triglyceride + Water Fats Oils

21. O O O = = = Another triglyceride… from stearic acid H | H—C—O—C—(CH2)16CH3 | H—C—O—C—(CH2)7CH=CH(CH2)7CH3 | H—C—O—C—(CH2)14CH3 | H from oleic acid from palmitic acid + 3 HOH

22. Neutralization Reaction Acid + Base Salt + Water Acetic Acid + NaOH Sodium Acetate + H2O O O + + H2O NaOH CH3 C CH3 C O- Na+ OH Try another one!!

23. Stearic Acid CH3(CH2)16COOH O CH3(CH2)16C OH

24. Review Acid + Base O + (CH2)16 NaOH CH3 C OH O + H2O (CH2)16 CH3 C O- Na+ Salt + Water

25. Review Fatty Acid + Base O + (CH2)16 NaOH CH3 C OH O + H2O (CH2)16 CH3 C O- Na+ Soap + Water

26. Soap • Generic term for the soluble salt of afatty acid

27. Salt of a Fatty Acid (Soap!!) O (CH2)16 CH3 C O- Na+

28. Salt of a Fatty Acid (Soap!!) How does a soap work? O (CH2)16 CH3 C O- Na+

29. Salt of a Fatty Acid (Soap!!) Polar or nonpolar? O (CH2)16 CH3 C O- Na+

30. Salt of a Fatty Acid (Soap!!) Polar or nonpolar? O (CH2)16 CH3 C O- Na+

31. Salt of a Fatty Acid (Soap!!) Polar or nonpolar? O (CH2)16 CH3 C O- Na+

32. Salt of a Fatty Acid (Soap!!) Polar or nonpolar? O (CH2)16 CH3 C O- Na+ NONPOLAR CHAIN POLAR (IONIC) END

33. Salt of a Fatty Acid (Soap!!) Different parts of the molecule behave differently! A molecule with dual personalities! O (CH2)16 CH3 C O- Na+ POLAR (IONIC) END NONPOLAR CHAIN

34. REVIEW - TYPES OF BONDS COVALENT NONPOLAR POLAR IONIC Low High Electronegativity Difference

35. Salt of a Fatty Acid (Soap!!) Squiggly Notation + NONPOLAR CHAIN POLAR (IONIC) HEAD

36. What about grease? What are its properties?

37. What is grease? A bunch of fats and oils!!

38. Polar or nonpolar?

39. O O O = = = Another triglyceride… from stearic acid H | H—C—O—C—(CH2)16CH3 | H—C—O—C—(CH2)7CH=CH(CH2)7CH3 | H—C—O—C—(CH2)14CH3 | H from oleic acid from palmitic acid + 3 HOH

40. From Crude Oil Polar or nonpolar?

41. Dirt and Grease A bunch of nonpolar molecules How does soap clean?

42. 1) The soap traps the grease water water Polar Head water GREASE Nonpolar Tail water water water water

43. Figure 5.21 (p. 249)

44. 2) The water washes away the soap + grease Why? Polar Head .. .. O H H Polar Molecule

45. 1) The soap traps the grease water water Polar Head water GREASE Nonpolar Tail water water water water

47. How do we make a soap?

48. O + (CH2)16 NaOH CH3 C OH Neutralize a fatty acid? O + H2O (CH2)16 CH3 C O- Na+

49. We don’t just have fatty acids sitting around in our world… Where can we get them?

50. Fats! We need to hydrolyze a fat!!