Properties of Water
Chapter 2
Pages 18-47
Marine Science
Ms. Flick
Vocab
1. Basins
2. Renewable resource
3. Nonrenewable
resource
4. Overfishing
5. Sublimation
6. Freezing points
7. Melting point
8. Boiling point
9. Variables
10.Independent variable
11.Dependent variable
12.Solvent
13.Solute
14.Solution
15.Solubility
16.Atom
17.Neutrons
18.Protons
19.Hydrogen bonding
20.Cohesion
Vocab Continued.
21.Hydrogen bonding
22.Cohesion
23.Surface tension
24.Salinity
25.Vaporization
26.Freezing
27.Condensation
28.Brackish
29.Estuaries
30.Neutral buoyancy
Our Oceans
• The ocean covers approximately 71% of Earth’s
surface
• Our planet’s ocean can be divided into four oceans:
–
–
–
–
The Pacific
The Atlantic
The Indian
The Arctic
• Basins-large water covered areas between
continents; commonly referred to as oceans
• Earth’s ocean contains 97% of the water on Earth
• That leaves only 3% of the planet’s water as fresh as
opposed to salt
• 2/3 of that freshwater is contained in ice in glaciers
and sea ice caps in Earth’s polar regions
Ocean’s Renewability
• The ocean is important for all living things and
influences many of Earth’s processes
• The ocean is a resource that replenishes itself
naturally over relatively short periods of time
– Renewable resource
• Some resources, such as natural gas and minerals, are
exhausted faster than they are naturally replaced
– Nonrenewable resources
• Just because the ocean is considered a renewable
resource doesn’t mean everything in it is
– Overfishing-humans extract fish at rates faster than they
can reproduce making the food source no longer
renewable
Activity 1 Procedure
1. Prepare two beakers-1 w/ cold water, 1 w/ warm water
2. Measure and record the temperature of each
3. Place 15 drops of blue food coloring into the cold water
and stir
4. What will happen if cold water (blue) from a pipette is
added to the warm water carefully down the side of the
beaker? Write down your hypothesis-if/then statement
5. Add droppers full of the cold blue water down the inside
wall of the warm water beaker
6. Drop some on one side-then the opposite side
7. Note: the dropper tip should be placed immediately
under the surface of the water
8. Write down your observations.
Activity 2
1. Prepare 2 beakers-1 w/ warm water and
1 w/ ice cubes
2. Measure the temperature of each
beaker’s contents and record
3. Place several ice cubes in the water
Discussion
1. How can you explain our observations of
Activity 1?
2. What are the ice cubes made of?
3. In Activity 1 the cold water stayed on
the bottom. If the ice is colder than the
water would you expect it to float on
the water?
4. What issues would their be in nature if
ice did not float on water?
Investigation 1:
Freezing, Melting, and Boiling
Follow the directions in your textbook on
pages 23-26 to complete this
investigation.
Write down your findings on your own
sheet of paper.
Investigation 2:
Surface Tension
Follow the directions in your textbook on
pages 26-27 to complete this
investigation.
Write down your findings on your own
sheet of paper.
Investigation 3:
Floating and Sinking
Follow the directions in your textbook on
pages 28-29 to complete this
investigation.
Write down your findings on your own
sheet of paper.
Investigation 4:
Solutions
Follow the directions in your textbook on
pages 30-31 to complete this
investigation.
Write down your findings on your own
sheet of paper.
Atoms
• Atom-the most basic particle of a unique
element that has the properties of that element
• Neutrons-no electrical charge
• Protons-a +1 or a positive 1 charge
• Around the dense nucleus of each unique atom
is a cloud of tiny, negatively charged electrons
• Look at figure 2.16-hydrogen atom
• Look at figure 2.17-oxygen atom
• Hydrogen and oxygen combine to make a water
molecule
Water Molecules
• Look at figure 2.19-water molecules
• Hydrogen bonding-the attraction between water
molecules
• Cohesion-the property of water making it attracted
to other molecules of water via hydrogen bonding
• It is cohesion that allows
water to form drops
• Surface tension-the
attraction between
molecules at a liquid’s
surface
Salinity
• Salinity-the measure of dissolved salts in
water
• Distilled water has no salinity
• Water is considered fresh if it contains 1 part
per thousand or less of salts
• The average salinity of the ocean is 35 parts
per thousand (35% salt)
Ocean Water
• Ocean water carries a lot of minerals
• The minerals come from:
– Land: freshwater in streams and rivers contains
salts and flows into the ocean
– Inside the Earth: volcanoes, vents, and other
processes at the seafloor spew minerals from
below Earth’s crust
– Atmosphere: carried by wind and deposited into
the ocean
Phase Changes
• Vaporizationliquid to gas
• Freezingliquid to solid
• Condensationgas to liquid
• Pure water boils at 100 degrees C
– 212 degrees F
• Pure water freezes at 0 degrees C
– 32 degrees F
• Salt water boils and becomes a gas at a slightly higher
temperature than freshwater
• Salt water freezes at a slightly lower temperature
Freshwater and Saltwater Meet
• Brackish-water that is somewhere between salt
and fresh
– Margrove forests and salt marshes
• Estuaries-where rivers meet the sea
– Nurseries of the sea; provide home for many species
of marine life
• Plants and animals living here can tolerate wide
ranges in salinity b/c their always changing
Neutral Buoyancy
• Some organisms float on top of the ocean
• Others live near its bottom
• Others make their homes throughout the
water column
• Organisms have features that assist them with
floating and sinking or moving up and downneutral buoyancy