1. Properties of Water Unit 2

2. I. Water Is A Solvent Solvent – substance doing the dissolving
Solute – substance being dissolved
Major difference in freshwater and sea water is presence of salt (NaCl)

3. II. Structure of Water and one oxygen. Pure H2O – two hydrogen
B. Salt Water – Six elements
and compounds comprise about 99% of sea
salts.

4. III. pH of Water H2O can separate into H+ and OH- ions.
The presence of these ions cause water to become acidic or basic.
pH of pure water – 7
“neutral”

5. IV. Dissolved Oxygen in Water
Oxygen is found in water even though it does not dissolved easily.
Dissolved oxygen is measured in parts per million (ppm).
Ocean water can hold from 1 to 12 ppm depending on the temperature of the water.
(oxygen in air is 200 ppm)

6. V. Sea Water
Ocean water is made up of about 96.5 percent water molecules and 3.5 percent NaCl (table salt).
B. Calcium Carbonate is also a common compound found is the seas.

7. VI. Salinity Oceanic waters typically have
35g of salt dissolved in 1000g of water (3.5%).
B. Salts accumulate in the oceans as rain leach sediments from
the land.

8. VII. Temperature Ocean water temperatures vary between -2 to 30°C.
B. Temperatures below 0ºC are
possible because salt water freezes at colder temperatures than pure water.

9. VIII. Pressure A. Organisms on land experience atmospheric pressure.
B. Marine organisms experience water pressure and atmospheric pressure.

10. C. Units of Pressure 1. Atmospheric pressure: atm
0m 10m 20m 30m 40m 50m 60m 70m 80m 90m
1atm atm
C. Units of Pressure
1. Atmospheric pressure: atm
2. With each 10m (33ft) of increased depth, another atmosphere of pressure is added.

11. IX. Buoyancy -
an upward force exerted
by a fluid an object is in.

12. X. Density A. Mass of a substance per unit of volume.
B. Formula: D= m/v
C. Unit: g/ml or g/cm3 (ml = cm3)
D. Density of Pure H2O = 1 g/ml
(impurities in water cause the density to increase)

13. E. Principle of Density
1. Objects of greater density than the fluid they are in – will sink in the fluid.
2. Objects of lesser density than the fluid they are in – will float in the fluid.