Liquid Water Ice Water Vapor

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Name: ____________________________________________________
Block: _________
Study Guide Due:
Test Dates:

A day – January 3rd (the FIRST day
back from break)!!!
 A day – January 5th

B day – January 4th (the SECOND day
back from break)!!!
 B day – January 6th
Date: _______________________
1. What two elements make up one molecule of water? (pg._____)
2 atoms of Hydrogen and 1 atom of Oxygen
2. What does it mean when we say that water is a POLAR molecule? EXPLAIN! (pg._____)
Water is a polar molecule because it has one positive side and one negative side.
3. Use the space below to draw a model of a water molecule. Be sure to label your model with the
following: (pg._____)
a. Hydrogen
+
H
H
b. Oxygen
c. Positive (+)
O
d. Negative (-)
4. Fill in the following chart with the missing information. (pg._____)
Term
Cohesion
Surface tension
Adhesion
Definition
The attraction of water to itself
(when water molecules stick to
each other)
Cohesion at the surface of the
water (when water molecules
stick to each other at the surface
of water)
The attraction of water to other
materials (when water molecules
stick to other materials)
Draw and Describe an
Example
5. To the right is an example of surface tension in action. EXPLAIN what is
happening. (pg._____)
The water molecules are sticking together very tightly at the surface. The
weight of the paper clip is being supported by the water’s
surface tension. The top layer of the water behaves as if it
was an elastic or stretchy skin. This is surface tension. Surface
tension is caused by the attraction of water molecules to other
water molecules.
6. Capillary action is what causes tall redwood trees to be able to receive water all the way at the top.
What properties of water allow this to happen? (pg._____)
Cohesion and adhesion working together; adhesion is when the water sticks to the inside of the
tree and cohesion is when water molecules stick to each other. When these properties happen at
the same time it allows the water to “climb” up the tree.
7. Why is water considered the universal solvent? (pg._____)
Water is considered the universal solvent because it can dissolve more substances than any other
compound.
8. What property of water allows it to dissolve so many things? (pg._____)
Water is a polar molecule which allows it to stick to and dissolve so many different substances.
9. In the boxes provided, draw pictures of the arrangement of water molecules as a liquid, solid, and gas.
(pg._____)
a. Circle the box where the molecules are moving the fastest!!!
solid
liquid
gas
10. Fill in the following chart with the correct temperatures. (pg._____)
Water
Freezes at:
0o C
Boils at:
100o C
11. The following chart shows water changing from one state to another. For each example, write “adding
heat” or “removing heat” to describe how the water is changing from one state to the other.
(pg._____)
Phase Change
Adding Heat or Removing Heat?
Ice
Liquid water
Adding heat
Water vapor
Liquid water
Removing heat
Liquid water
Ice
Removing heat
Liquid water
Water vapor
Adding heat
12. Match the property with the correct phase or phases of water. (pg._____)
Choices:
(You can choose more than one)
Liquid Water
Takes the shape of the container
Ice
Liquid water (& water vapor)
The water molecules are moving the slowest
The molecules can move freely and bounce off each
other
Water molecules are moving the fastest
Water Vapor
Ice
Liquid water & water vapor
Water molecules have the largest temperature
range (0 -100 ˚C) in this phase.
Water vapor
Liquid water
13. The glass of water to the right shows two phases of water, which two phases do
you see? (pg._____)
liquid water & solid ice
14. In the glass of water shown to the right, the ice is floating on top of the water.
Which phase of water appears to be LESS dense than the other? (pg._____)
The ice is less dense than the water; that’s why the ice is floating.
15. Using your answer from question #14, EXPLAIN WHY that phase is LESS dense than
the other. (pg._____)
Ice is less dense than liquid water because as water freezes it expands and forms a
rigid geometric pattern (hexagonal chain). This creates more space between the molecules than in
the liquid phase. This space causes the ice to become less dense and float on liquid water.
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