3. Roughly 70 percent of an adult’s body is made up of water. By the time a person feels thirsty, his or her body has lost over 1 percent of its total water amount. Although a person can live without food for more than a month, a person can only live without water for approximately one week. Your brain is 75-85% water and plays a vital role in your body's response to dehydration. It controls water intake through altering thirst and varying the water excretion from your kidneys. http://science.howstuffworks.com/environmental/earth/geophysics/h2o3.htm http://www.healthy-water-best-filters.com/human-water-cycle.html http://fiteats.wordpress.com/page/3/ http://www.mpip-mainz.mpg.de/documents/akbu/pages/ssci.html

4. 8P 8N 1P 0N 1P 0N

8. Hydrogen Bonding Simulation

12. Images from: http://understanding-biology.blogspot.com/2010/01/floating-paper-clip-cohesion-surface.html

16. Water acts like a heat buffer for the globe.

17. Image from: http://www.wallpaperbase.com/landscape-iceberg.shtml

18. “Universal solvent”

19.  Solution = liquid consisting of uniform mixture of two or more substances › Two parts of a solution:  Solvent = liquid (dissolving agent)  Solute = substance dissolved › EXAMPLE:  Water = solvent Koolaid powder/sugar = solutes Kool-aid = solution

20.  Remember the rule to make a solution: “Like dissolves like.” › Since water is polar, it will dissolve ions and other polar substances (like salt!) Na+ Cl- › Hydrophilic = Water Lover › Water will NOT dissolve nonpolar substances

21.  Electrons are shared equally in nonpolar molecules.  Oil is an example of a nonpolar molecule.  It does not form hydrogen bonds.  Like dissolves like, therefore, oil (nonpolar) does not mix with water (polar).  Nonpolar molecules are hydrophobic (“afraid of water”) because they do not mix with water.

23. Simulation found at: http://www.sumanasinc.com/webcontent/animations/content/propertiesofwater/water.html

24. surface tension =A measure of how difficult it is to stretch or break the surface of a liquid. Water has a high surface tension because of the hydrogen bonding of surface molecules Electronegativity=The attraction of an atom for the electrons of a covalent bond Electronegativity is the tendency for an atom to pull electrons toward itself. Two atoms of the same element have equal electronegativities; in a covalent bond they share electrons equally, forming a nonpolar covalent bond.