1. End Show Slide 1 of 44 Copyright Pearson Prentice Hall Biology

2. End Show Slide 2 of 44 Copyright Pearson Prentice Hall 2-2 Properties of Water

3. End Show 2-2 Properties of Water Slide 3 of 44 Copyright Pearson Prentice Hall The Water Molecule A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms.

4. End Show 2-2 Properties of Water Slide 4 of 44 Copyright Pearson Prentice Hall The Water Molecule Water Molecule

5. End Show 2-2 Properties of Water Slide 5 of 44 Copyright Pearson Prentice Hall The Water Molecule Hydrogen Bonds Because of their partial positive and negative charges, polar molecules can attract each other.

6. End Show 2-2 Properties of Water Slide 6 of 44 Copyright Pearson Prentice Hall The Water Molecule Cohesion is an attraction between molecules of the same substance. Because of hydrogen bonding, water is extremely cohesive.

7. End Show 2-2 Properties of Water Slide 7 of 44 Copyright Pearson Prentice Hall The Water Molecule Adhesion is an attraction between molecules of different substances.

8. End Show 2-2 Properties of Water Slide 8 of 44 Copyright Pearson Prentice Hall Acids, Bases, and pH A water molecule is neutral, but can react to form hydrogen and hydroxide ions. H 2 O   H + + OH -

9. End Show 2-2 Properties of Water Slide 9 of 44 Copyright Pearson Prentice Hall Acids, Bases, and pH The pH scale Chemists devised a measurement system called the pH scale to indicate the concentration of H + ions in solution. The pH scale ranges from 0 to 14.

10. End Show 2-2 Properties of Water Slide 10 of 44 Copyright Pearson Prentice Hall Acids, Bases, and pH At a pH of 7, the concentration of H + ions and OH - ions is equal. The pH Scale Human blood Milk Sea water Normal rainfall Pure water

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