1. Ocean Properties and Chemistry

2. Ocean Properties

3. Physical Properties of Water
Importance of water: We are made of 70% of water and some ocean organisms are made up to 90% water

4. Polar
Excellent solvent
Hydrogen bonds (makes water sticky= cohesion, keeps water stable at different temps.
Specific heat (ability to hold onto heat)
Ability of light to penetrate water

5. Ability of light to penetrate water
150 meters
900 meters
1000 meters or more

6. Chemical Properties of Water
Acidity and alkalinity
pH scale
0-7 acidic
7 neutral
7-14 alkaline
Seawater is slightly alkaline between on average
Acid:_amount of hydrogen ions H+
Base:_amount of hydroxide ions OH-

7. More Chemistry

8. Importance of pH in the oceans
When carbon dioxide (CO2) is absorbed by seawater, chemical reactions occur that reduce seawater pH, and saturation states of biologically important calcium carbonate minerals

9. No calcium Carbonate, No shells
Projected sea water in 2100 will dissolve the shells of all sea life 

10. Gases in Seawater Gases from biological processes Oxygen-minimum zone
Photosynthesis________
Cellular respiration______
Decomposition________
Oxygen-minimum zone
Solubility of gases in seawater
Environmental variables affect amount of gases:__________

11. Oxygen Levels In the ocean 700 m -1200 m OMZ

12. Composition of Seawater
Ionic salts
Sodium (Na+)
Magnesium (Mg2+)
Calcium (Ca2+)
Potassium (K+)
Chloride (Cl-)
Sulfate (SO42-)
Trace elements

13. Salinity
Salinity: How much salt is dissolved in water, it is measured in ppt (parts per thousand) oceans are around 30 ppt
3.5% salt and 96.5% water by mass

14. Salinity Salinity changes due to: evaporation: high salinity
precipitation and runoff: low salinity

15. Salinity in Bays and Estuaries
Less than 25 ppt is called brackish, meaning a combination of salt water and fresh water.
Bays and Estuaries have Brackish water

16. Tides (Changes Salinity)
Low Tide: Low salinity
High Tide: Normal Salinity
(Bays Estuaries)

17. Physical Properties of Water
List 5 physical properties of ocean water
2. What is Salinity? Where does it change in the oceans?
How does the oxygen content change in the ocean?
What is the difference between an acid and a base?
Describe how light travels in water.
Give an example of a polar molecule and how it dissolves other polar substances.