The Physical and Chemical Properties of Water

 

The Water Molecule

     H2O - dipole structure

     Hydrogen Bonds

 

     Solvent power & high heat capacity

Changes of State

     Temperature and Heat

    Average kinetic energy versus total kinetic energy

 

     The physical states of water

    Liquid, solid, and gas

    H bonds = high heat capacity

    Latent heat of fusion

    Latent heat of vaporization

Other consequences of H bonds

     Cohesion

     Surface Tension

     Viscosity

H2O Density

     1 g/cm3

 

     Temperature and density

 

     How does salinity influence density?

Transmission of Energy

     Heat - Conduction, convection, radiation

     Light

     Visible light

     Refracted, absorbed, scattered

     Attenuation

     How far does light penetrate into the ocean

     Photic Zone

The Chemistry of Seawater

            Acidity and alkalinity - H+ and OH-

     pH

     pH of Seawater = 7.8

 

            Why is seawater buffered?

Salinity

     Solvent power

 

     Disolved ions

Salinity

amount of dissolved ions in seawater..

 

-> normal salinity = 3.5% or 35 parts per thousand (ppt)

 

Tropics = lowest salinity->high precip.=> 34.5

Subtropics=highest salinity ->high evaporation => 36

 

Why does this surface pattern exist?

Salinity

     Where does the salt come from?

 

     Why is salinity so stable?

 

Chemistry of Seawater

     Major constituents

     Trace elements

     Conservative

     Principle of Constant Proportion

Chemistry of Seawater

     Gasses

        N2, O2, and CO2

 

     Why are concentration of O2 high but CO2 low in the upper 100 m?

 

     Why does O2 reach a minimum between 200 and 800 m?

 

     Temperature, salinity, and pressure

 

 

CO2 and O2

     The Carbon Cycle

     The biological pump - deep ocean = carbon sink

 

     The Oxygen Balance

    Photosynthesis <=> Weathering

Nutrients

     N, P, and Si

     Nonconservative elements

     Limiting elements