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T.O.D: (table from old study guide) take home essay?. Chapter 3: Water. Water’s Polarity Cohesion, moderation of temperature, ice is less dense, universal solvent Dissociation of water molecules pH. WATER: the stuff of life!. www.pascochamber.org/ visitorInfo.htm.
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T.O.D:(table from old study guide)take home essay? Chapter 3: Water Water’s PolarityCohesion, moderation of temperature, ice is less dense, universal solvent Dissociation of water moleculespH
WATER:the stuff of life! • www.pascochamber.org/ visitorInfo.htm www.hd.org/Damon/photos/natural-science/&h=254&w=243&prev=/images
Water’s polarity and hydrogen bonds • Account for its unique properties that contribute to the fitness of Earth’s as an environment for life.
Cohesion/Adhesion • Cohesion is water’s attraction to water • Adhesion is water’s attraction to other substances • Surface tension • Water transport in plants, up ___ tubes
Stabilize temperatures • WHY? • High specific heat • Water moderates global and organismal temperatures • Evaporative cooling is important for animals as well as plants
Expansion upon freezing • Because of Hydrogen bonding … • 0° C Ice is less dense than liquid water • When is water most dense? • If this didn’t happen, bodies of water would freeze solid
VersatileSolvent: • Ex: Salt and water • Ionic and polar com-pounds dissolve in water
Even very large molecules like proteins dissolve in water as long as there are areas of ionic or polar bonds.
The pH scale • pH=The measure of H+ and OH- in a solution. • Scale 0-14… • Acids=increase the H+ concentration • Bases=reduce the H+ concentration
pH = -log[H+] • Neutral = 10-7[H+] • Ex: pH 9 has H+ concentration of 10-9 M and an OH- concentration of 10-5 M • Practice problems… • Buffers • Acid rain
Ch.1-4 Quiz study tips: • Practice questions at the end of the chapters • The test’s CD ROM demonstrations and practice questions • Study your HW notes and class notes
Sources • Campbell, Reece, Mitchell. Biology, 5th Ed. 1999, Chap-ter one. Pgs. 1-21. • Campbell, Reece, Mitchell. Biology, 5th Ed. 1999, Presentations CD-ROM. • Click art CD-ROM, Broderbund.