Kaitlyn Johnson
Block 2A
Marine Science
 By
mass, seawater is about 96.5% water
and 3.5% dissolved substances (various
types of salts.)
 The
world ocean contains 5.5 trillion tons
of salts.
 Salinity-
the total quantity (or
concentration) of dissolved inorganic
solids in water.
 The oceans salinity (by mass) is about
3.5%
 Sodium and Chloride are the most
abundant ions
2) How does the addition of ions to water change the
properties of water?
There are 4 ways the ions effect the water, which are called
Colligative properties- “properties of solutions”
(Salinity- measure if
dissolved solids in sea
water: (ex.) NaCl sodium
chloride)
Heat & Cool
“Heat capacity of water decreases
with salinity increasing”
-less heat is required in sea water than
fresh water
(more salinity, the faster it gets hot)
-ex. boiling water
“As salinity increases,
freezing point of water
drops, and salt acts as a sort
of anti freeze”
-ice forms at a lower temperature
in sea water than freshwater
-ex. lakes
6
Evaporation & Osmosis
“Dissolved salts attract
water molecules, making
evaporation slower”
-Water evaporates slower in sea
water than fresh water
-(e.x swimmers in a pool vs
ocean drying)
“-Osmotic pressure
-salinity’s different in
environment verses salinity
in a cell.
-key factor of transmitting
water in and out of cells”
Otherwise known as
Forchahmmers principle
It is the law stating
that aside from the
water salinity there
are always similaritys
in other mixed
minerals
•
•
•
Dissolved crustal rock (sodium)
•
Breaking up of the cooled igneous rocks of the Earth’s crust
Volcanoes
•
Solid and gaseous materials that escaped from the earths
crust through volcanic vents
Rift vents
By Jimmy DeLuca
What is it?
 Chemical equilibrium- The proportions and amounts




of dissolved salts per unit of volume.
Whatever goes in the ocean must come out.
Ions are added to the ocean at the same rate that they
are being removed.
Dissolved particles are brought down into the
sediment at the bottom of the ocean.
This theory helps explain why the ocean is not growing
saltier.
By Erin Bieger
 About
48 percent of dissolved gas in
seawater is nitrogen.
 Upper layers of ocean water are saturated
with nitrogen gas.
Percent of gas in atmosphere
 Nitrogen- 78.08%
Atmosphere
 About
38 percent of gas dissolved in the
ocean is oxygen.
 The small amount of oxygen is vital resource
for animals that extract oxygen in the gills.
Percent of gas in atmosphere
 O- 20.95%
 Atmosphere
 The
amount of carbon dioxide in the
atmosphere is small because CO’2 is a great
demand by photosynthetic plants.
Percent of gas in atmosphere
 CD-0.035%
 Atmosphere ,respiration
By: Kaitlyn de la Torre
 Sea
water is slightly Alkaline, its average PH is about
8.0.
 The ocean acts as a buffer, if more acid is added to
the ocean it produces more alkaline to keep the PH
balanced.

 If
Similar to homeostasis
Sea water was too acidic seashells and coral reefs
would weaken and dissolve.
 Acidity is important in sea water because it decays
bacteria and remains of animals.