The Properties of Water “the liquid of life”

1. If all the rain drops were lemon drops and gum drops, oh what a rain that would be The Properties of Water “the liquid of life” Ice, Ice, baby Cry me a river Raining on Sunday I’m H20 intolerant It’s Raining men!!! You’re as cold as ice Singing in the rain Don’t go chasing waterfalls Water is the essence of wetness and wetness is the essence of beauty Smoke on the water Rain drops on roses..whiskers on kittens I can see clearly now, the rain is gone Rain drops keep falling on my head Like a bridge over troubled water Let the rain fall down and wake my dreams Its like rain on your wedding day Walking on water Now that’s some high quality H2O Water water everywhere and not a drop to drink Its raining its pouring the old man is snoring The fog creeps in on little cats feet Water off a ducks back When Chuck Norris goes swimming, he doesn’t get wet… the water gets Chuck

2. Property of Water Definition and Mechanics Biological Implications Water molecules stick together due to H bonds Cohesion Transpiration in plants Water molecules stick to other polar molecules due to H bonds Transpiration in plants Capillary movement Adhesion Water does not change temperature quickly due to hydrogen bonds preventing changes in molecular movement “cooler by the lake” Blood used as heat transport High Specific Heat Water absorbs high quantity of heat before it turns to a gas due to hydrogen bonds Evaporative cooling (Sweating) Temperature stability in water High Heat of Vaporization Ice floats because the hydrogen bonds maximize the distance between molecules Less Density as a Solid Keeps Aquatic organisms alive during the winter http://www.youtube.com/watch?v=k310d_egbFk Insects walk on water Water stays together as “drops” Hydrogen bonds keep water molecules connected when exposed to air High Surface Tension YouTube - Jesus lizard The polar nature of water can dissolve any polar molecule or isolate polar part on large molecules A) Hydrophilic : Water loving (polar) B) Hydrophobic: Water hating (non-polar) Living things are 75% water. Most biologically active molecules are hydrophilic Solvent of Life

3. Water: Fun things we do with it Real or Fake? Lack of injury to participants brought to you by Hydrogen Bonds and the Emergent Properties of Water

4. Water and pH 1. What is pH? The measurement of the Hydrogen (or hydronium) ions found in a hydrophilic solution 2. Where do the H+ come from? A small % of water molecules dissociate into Hydronium(H3O+) and Hydroxide (OH-) ions HOH H+ + OH-

5. 3. How is pH measured? pH = -log H+ Pure water H+ = .0000001 -7 or = 1x10 -7 -log of = 7 1x10 Therefore: The pH of pure water is 7 The numbers on the pH scale are in 10X increments Increasing H+ (increasing Acid) Increasing OH- (increasing Basic) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

6. 4. What does pH have to do with Biology? A) The pH of the environment can influence biologically active molecules 1) influence chemical reactions 2) affect the interactions of hydrogen bonds 3) determine the structure of proteins

7. 5. How do living organism control pH? a) Living organism use “buffers” to regulate pH b) Buffers work by donating or accepting H+ from the environment Increasing OH- H2CO3 HCO3 + H+ Increasing H+ Examples of buffers 1) organic “weak” acids 2) some proteins (albumin)

8. Slide 2

9. Ice Water Steam Slide 2

10. Water Dissolving Large Molecules With Many Polar Functional Groups Water Dissolving Ionic Molecules Slide 2