Water Properties

1
Water Properties

• Polar Covalent Bond
• Cohesive behavior
• Adhesive behavior
• High Surface Tension
• Capillary action

2
Polar Covalent Bonds

• Unequal sharing of electrons
• Oxygen has a stronger pull on the electrons, so
  they stay closer to the Oxygen atom
• This makes oxygen slightly negative
• Hydrogen has less of a pull on the electrons, so
  they are farther away from the Hydrogen atoms
• This makes hydrogen slightly positive

3
Polar water molecules can Surround and Separate
This means that water is able to dissolve things!
4
Hydrophilic vs. Hydrophobic

• Hydrophilic water loving substances that
  have an affinity for water
• Towels would be considered hydrophilic because
  they readily absorb water
• Hydrophobic water fearing substances that
  fear or repel water form clusters
• Oil is hydrophobic because of the way it forms
  droplets in water

5
Cohesion

• The attraction of water to other water molecules
  
• Results from hydrogen bonding

6
Meniscus

• a curve in the surface of a liquid

Waters meniscus curves up around the edges
because of waters adhesive property to the
graduated cylinder.
7
Cohesion and Adhesion

• Adhesion is the attraction of different
  substances to one another
• Water to the side of a straw water in the straw
  is higher than the level of water around the
  straw
• Cohesion and adhesion work together to create
  capillary action the ability of water to move
  upward against the force of gravity.

8
Capillarity in plants -- xylem
9
Surface Tension

• Measure of how difficult it is to stretch or
  break the surface of a liquid.
• Water behaves as if coated with an invisible
  film.
• Some organisms can stand, walk, or run on water
  without breaking the surface
• Water striders (insect)

10
(No Transcript)