Properties of Water

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Properties of Water (part 1)
http//64.5.130.54/videos//26814//chp926042_256.mo
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Textbook pages 50-58
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SEVEN PROPERTIES OF WATER
POLAR MOLECULE -
negative positive ends
SURFACE TENSION -
tightness across (top) of water
stickiness that causes water molecules to
climb up a tube
CAPILLARY ACTION -
causes MANY substances to dissolve (break apart)
UNIVERSAL SOLVENT -
NORMALLY PRESENT IN ALL THREE STATES -
Water is the ONLY substance on Earth that can
normally be found in all three states. (solid,
liquid, gas)
HIGH SPECIFIC HEAT -
does not gain or lose heat quickly
EXPANDS (takes up more space) WHEN FROZEN -
Most liquids contract (take up less space) when
frozen.
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1) Water is made up of POLAR MOLECULES

• Hydrogen end Slightly positive charge
• Oxygen end Slightly negative charge

The negative and positive ends attract each
other, making water molecules very COHESIVE
(sticky).
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2) Because its molecules are cohesive, water
has a high SURFACE TENSION.
Surface tension is the tightness across the
surface of the water that is caused by the polar
molecules pulling on each other.
This is what allows some insects to walk on
water.
Draw a picture of an insect walking on the
water in your notes.
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3) Waters cohesiveness also gives it a property
called CAPILLARY ACTION.
Capillary action is what makes your drink look
like it is climbing higher inside your straw than
in your glass!
A capillary is a thin tube, like a straw, a test
tube, or one of your veins.
Draw this in the box.
The water molecules climb the sides of a tube
because of their cohesiveness. Their positive
negative charges are attracted to the charges on
the sides of the tube.
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4) Because many things will dissolve in it,water
is called the UNIVERSAL SOLVENT.
The charged ends of the water molecules attract
the molecules of other polar substances, pulling
them apart!
A SOLVENT is a substance that makes other
substances dissolve (break apart).
Some things that water can dissolve sugar
salt soap bleach oxygen carbon
dioxide and many more!
Name some things that water cannot dissolve.
Oil, Wax
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To be continued