Properties of Water

1
Properties of Water

• 2.2

2
Water Water Water

• Polar Molecule has uneven distribution of
  electrons giving it a positive and a negative end
  
• Partially due to the size differences between
  oxygen and hydrogen.
• Oxygen will take on a slight negative charge and
  hydrogen will take on a slight positive charge

3
The Universal Solvent

• Waters polar nature makes it very effective in
  dissolving other substances, including ionic
  compounds into ions

4
Forms Hydrogen Bonds

• Holds 2 H2O molecules together
• Results in Cohesionattractive force between like
  particles ex surface tension
• Can result in Adhesionattraction on unlike
  substances
• Ex capillarity-ability for water molecules to
  move against gravity (think blood)

5
Specific Heat

• Water needs to lose or gain high amounts of
  energy to break bonds and change phases
• How could this be helpful to organisms?
• Keeps cells at even temperatures during
  environmental changes!!!

6
Solutions and Suspensions

• Solution all components evenly distributed
• EX Saltwater
• Salt is the SOLUTE
• Water is the SOLVENT
• Suspension mixture of water and non dissolved
  particles
• EX Blood (water and cells), Fog, Muddy Water,
  Paint, Flour in water

7
Acids and Bases Review

• pH Scale indicates the concentration of H ions
  in solution
• 0?14
• 0-6.9 ACID
• 7 Neutral
• 7.1-14 BASE

8
Acids, Bases, and Buffers

• Acid makes H ions in solution
• pH- below 7
• The lower the number, the stronger the acid
• fruit juice, acetic acid (vinegar), HCl, battery
  acid
• Base makes OH- ions in solution
• pH- above 7
• The higher the number, the stronger the base
• Seawater, ammonia, bleach, oven cleaner, lye
• Buffers weak acids/bases that can react with
  strong acids/bases to prevent major pH changes

9
Diffusion

• Net movement of molecules from hi to lo
  concentration
• http//lessons.harveyproject.org/development/gener
  al/diffusion/diffnomemb/diffnomemb.html
• http//www.biosci.ohiou.edu/introbioslab/Bios170/d
  iffusion/Diffusion.html