1. 2.3 Chemistry of Water

2. Properties of Water

3. Properties of Water
Water has a high heat capacity.

4. Properties of Water Water has a high heat capacity.
A calorie is the amount of heat energy needed to raise the temperature of 1g of water 1°C.

5. Properties of Water
Water is a solvent.

6. Properties of Water
Water molecules are cohesive and adhesive.

7. Properties of Water Water molecules are cohesive and adhesive.
Water molecules cling together because of hydrogen bonding (cohesion).

8. Properties of Water Water molecules are cohesive and adhesive.
Water molecules cling together because of hydrogen bonding (cohesion).
Water’s positive and negative poles allow it to adhere to polar surfaces (adhesion).

9. Properties of Water Water molecules are cohesive and adhesive.
Water molecules cling together because of hydrogen bonding (cohesion).
Water’s positive and negative poles allow it to adhere to polar surfaces (adhesion).
Water is an excellent transport system, both outside and within living organisms.

10. Properties of Water
Water has a high surface tension

11. Properties of Water Water has a high surface tension
This allows some insects to walk on the surface of a pond or lake.

12. Acids and Bases

13. Acids and Bases
When water ionizes, it releases an equal number of hydrogen ions (H+) and hydroxide ions (OH-).

14. Acids and Bases

15. Acids and Bases
Acidic Solutions (High H+ Concentrations)

16. Acids and Bases Acidic Solutions
Acids are substances that dissociate in water, releasing hydrogen ions (H+).

17. Acids and Bases Acidic Solutions HCl H+ + Cl-
Acids are substances that dissociate in water, releasing hydrogen ions (H+).
An example:
HCl H+ + Cl-

18. Acids and Bases
Basic Solutions (Low H+ Concentrations)

19. Acids and Bases Basic Solutions
Bases are substances that dissociate in water, releasing hydroxide ions (OH-) or take up hydrogen ions (H+).

20. Acids and Bases Basic Solutions NaOH Na+ + OH-
Bases are substances that dissociate in water, releasing hydroxide ions (OH-) or take up hydrogen ions (H+).
An example:
NaOH Na+ + OH-

21. Acids and Bases

22. Acids and Bases
The pH Scale

23. Acids and Bases
The pH Scale
Ranges from

24. Acids and Bases The pH Scale Ranges from 0 - 14
A pH below 7 is acidic [H+] > [OH-]

25. Acids and Bases The pH Scale Ranges from 0 - 14
A pH below 7 is acidic [H+] > [OH-]
A pH above 7 is alkaline [OH-] > [H+]

26. Acids and Bases The pH Scale Ranges from 0 - 14
A pH below 7 is acidic [H+] > [OH-]
A pH above 7 is alkaline [OH-] > [H+]
A pH of 7 is neutral [H+] = [OH-]

27. The pH Scale

28. Acids and Bases The pH Scale
Each unit change in pH represents a change of 10X

29. Buffers and pH

30. Buffers and pH
A buffer is a chemical(s) that keeps pH within normal limits.

31. Buffers and pH
A buffer is a chemical(s) that keep pH within normal limits.
Bicarbonate ions (HCO3-) and carbonic acid (H2CO3) found in human blood buffers the pH to 7.4

32. Buffers and pH OH- + H2CO3 HCO3- + H2O
If hydrogen ions (H+) are added to the blood, this reaction occurs:
H+ + HCO H2CO3
If hydroxide ions (OH-) are added to the blood, this reaction occurs:
OH- + H2CO3 HCO3- + H2O

33. 2.4 Organic Molecules

34. 2.4 Organic Molecules Always contain: Carbon (C) and Hydrogen (H)
A carbon atom may share electrons with another carbon atom

35. 2.4 Organic Molecules Always contain: Carbon (C) and Hydrogen (H)
A carbon atom may share electrons with another carbon atom

36. 2.4 Organic Molecules Many molecules of life are macromolecules.
(macromolecules contain many molecules joined together)

37. 2.4 Organic Molecules Many molecules of life are macromolecules.
(macromolecules contain many molecules joined together)
Monomers: Simple organic molecules that exist individually
Polymers: Large organic molecules form by combining monomers

38. 2.4 Organic Molecules

39. 2.4 Organic Molecules
A meal containing carbohydrates, lipids, and proteins.

40. 2.4 Organic Molecules
Cells have mechanisms of joining monomers to build polymers

41. 2.4 Organic Molecules
Cells have mechanisms of joining monomers to build polymers

42. 2.4 Organic Molecules
Cells have mechanisms of joining monomers to build polymers
Dehydration Reaction: an -OH and -H are removed
Hydrolysis Reaction: the components of water are added

43. 2.4 Organic Molecules