DO NOW
• Why is water a polar molecule?
– Explain using a minimum of 3 complete
sentences.
– MUST include the following:
•
•
•
•
Electrons
Polar
Covalent bond
Hydrogen bond
p. 6 Climbing Property of Water
• CHROMATOGRAPHY: • Black is
Colors are separated
composed of all
by densities. Less
the colors.
dense colors go to
Paper has
the top.
pores,
open
spaces
• Capillary action cohesion (water to
water) + adhesion
(water to paper)
• Polar water + polar
ink (dissolves)
p. 8 #6 Oil is hydrophobic
• Oil and water do not mix.
• H-bonding is only in polar
Oil is on top
polar
Non-polar
nonpolar
Water is
on bottom
Polar
polar
#5 Likes dissolve likes
Polar dissolves polar, but not
nonpolar
• Cell membrane is also amphipathic (polar
+ nonpolar)
Inside the cell membrane
p. 9 # 6Food coloring dissolves in
water.
• Water is polar +H-bonds
• Food coloring is polar.
• Makes a solution (water surrounds
the dye)
• Oil is nonpolar (no charge).
• And no H- bonds.
Polar molecules dissolve
polar molecules.
Dissolving
• A solute
surrounds the
molecules of
a solvent to
make a
solution
Stirring oil and water
• The oil will go back to being
separate from the water.
Interpret #6 Getting rid of oil on
water
HowStuffWorks "How do you clean
• Detergent
breaks up the
oil into very
small droplets.
up an oil spill?“ (pick a video)
Burn Off
Booms
Hi-pressure
water
Slick Sack
• Absorbent
pad
Hand washing
Oil Spills
Problems
•
•
•
a. dead sea life
b. human life ills
c. cost of clean-up
p. 9 Interpret 5 Amphipathic
(bipolar)
• molecules have (hydrophobic)
nonpolar end and to attract oil
structure, but also have a
region that is polar (hydrophilic)
attracts water to wash it away.
Like detergent.
Soap is a surfactant
• That reduces the surface tension
• Breaks the cohesion of water molecules