Download Surface tension is explained by water`s ability to form hydrogen

Jesus Lizard (Basilisk Lizard)
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Surface tension is explained
by water’s ability to form
hydrogen bonds. Water isn’t
attracted to air so molecules at
the surface tend to be drawn
into the body of the liquid.
This can allow things to “rest”
on the surface without sinking!
Surfactant
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Water’s surface tension can be decreased by
adding surfactant.
Surfactant is a wetting agent such as soap or
detergent that gets its name from surface
active agent.
Lung Surfactant: A fluid secreted by the cells
of the alveoli (the tiny air sacs in the lungs)
that serves to reduce the surface tension of
pulmonary fluids; surfactant contributes to the
elastic properties of pulmonary tissue.
Think About It?!?!
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On October 27, 1915, the British Imperial
Trans-Antarctic Expedition ship Endurance
was crushed by pack ice and sank, leaving
the members of the expedition to float on ice
floes for five months!! Bbbrrrrr Today,
icebreakers are used to open a safe path for
navigation through floating pack ice. What
property of water allows its solid phase, ice,
to float in its liquid phase???
Evaporation and Condensation
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Because of hydrogen bonding water
absorbs a large amount of heat as it
evaporates or vaporizes. (heat of
vaporization or condensation)
Bonds must be broken before water
changes from liquid to gas.
Steam carries a great deal of energy with it.
Evaporation and Condensation
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Rates of evaporation and condensation are very
important to regional temperature on Earth. Think
heat, cooling and rain cycles.
When water molecules separate, energy is required
to break hydrogen bonds. During melting or
evaporation, the temperature of either doesn’t rise
because the evergy is used to accomplish the phase
change. The amount of energy used during these
phase changes is returned to the environment when
the molecules reform hydrogen bonds as they
condense or freeze.
Solvents and Solutes
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Solvents: the dissolving medium of a
solution. Ex: Water is the universal
solvent. You can dissolve most things in
water.
Solute: the dissolved particles in a
solution. Ex: salt in salt water
Solvation: the process that occurs when
a solute dissolves.
SOLVATION
Heterogeneous Aqueous Systems

Suspensions:
mixtures from
which particles
settle out upon
standing. Ex:
sand in water
Solid particles
in solution
Liquid
portion
Colloids

Colloids: heterogeneous mixtures
containing particles that are
intermediate in size between those of
suspensions and true solutions.
Tyndall Effect
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Tyndall Effect the
scattering of
visible light in all
directions. You
can see a beam of
light passed
through a colloid
just like a
sunbeam in a
dusty room.
Visible light
SMOG
TYNDALL EFFECT IS THE REASON YOU
SEE SMOG!