ch 6 oceanography
What is the heat capacity of pure liquid water?
1 cal/g
When water freezes, the bond angle between the oxygen and hydrogen changes from about ____ to _____.
105 to 109 this is why liquid to gas water expands and becomes more dense
At what temperature is the density of water the greatest?
4 degrees Celsius
How many calories of heat must be added to change a gram of ice to liquid water?
80
What is water's latent heat of fusion?
80 cal/g
The area of the ocean that lacks light is called?
Aphotic zone
How is heat measured?
Calories or Joules
Why do the equatorial regions have lower salinity that the Tropic of Cancer and Tropic of Capricorn to the north and the south of the equator?
Equatorial regions have more evaporation than precipitation. Tropical regions have more precipitation than evaporation.
What is defined as the measurement of energy produced by the random vibrations of atoms or molecules?
Heat
What type of strong bonds holds the hydrogen atoms to the oxygen atoms in water?
Hydrogen bonds
Hoe does Liquid water's heat capacity compare to other substances?
Liquid water has a high heat capacity in comparison to most natural substances, this is why it is able to absorb a lot of heat.
The thin film of sunlit water at the top of the surface zone is called what?
Photic zone
What areas lack a thermocline?
Polar waters
What characteristics define the pycnocline?
Rapid change in density with a slight change in depth
The bending of waves such as when light and sound leave a medium of one density and enters a medium of a different density is called?
Refraction
What causes density of the ocean to increase?
Salinity (salt)
How does salinity change as you travel from the equator toward the poles?
Salinity decreases (more salinity at equator and less at the poles)
What percentage pf the ocean is contained in the surface zone? the pycnocline? The deep ocean?
Surface zone = 2% Pycnocline=18% Deep ocean=80%
What is defined as an object's response to input or removal of heat?
Temperature
As heat is removed from a substance and moves from a gas phase to a liquid phase, and subsequently a solid phase, they become more dense. How does water behave?
The density of water increases as the temperature drops, however, once it hits its maximum point at 3.98 C the water continues to cool and because of they hydrogen bonds become more rigid and expands slightly because the molecules are held farther apart from one another, and becomes less dense as it continues to cool until it freezes and becomes ice, where the density decreases abruptly.
Why is the sand at the beach hotter than the ocean water on a hot summer day?
The heat capacity of the ocean is much larger than the heat capacity of the sand, therefore, the sand's temperature is much higher than that of the water.
How is heat stored and released in the ocean ?
The ocean absorbs light energy as heat during the day and releases the heat at night.
Describe the polar nature of water at each end.
The oxygen in the water is partially negative due to the unshared pairs of electrons and the two hydrogen molecules have a partially positive charge. This creates a bent shape in the water molecule.
Where does the photic zone penetrate the deepest on average?
Tropical waters
____________________________ has the capability of absorbing and releasing heat with very little change in temperature.
Water
From above, clear ocean water looks what color because this wavelength.
blue
Which wavelength of the visible spectrum of light transmits most efficiently?
blue=most efficient red=least efficient
Why is water cohesive and adhesive?
cohesion holds the hydrogen bonds together to create surface tension on water. Since water is attracted to other molecules, adhesive forces pull the water toward other molecules.
What type of weak bonds holds water molecules close together?
covalent bonds
If the temp in a seawater sample changes from 4C to 30C, what happens to the density to the sample?
decreases
How is temperature measured?
degrees
The temp of the ocean is highest at the ______ regions of the ocean and lowest at the _____ regions of the ocean.
equators, poles
The speed of light in water is 3/4 o f the speed in light of air. This has what affect on ocean water?
increase salinity
If salinity in a seawater sample changes from 32 0/00 to 36 0/00 what happens to the density oof the sample?
increases
What happens to the speed of sound in the ocean?
increases as temp and pressure increases
What visible spectrum of light is transmitted least/most efficiently in the ocean?
most=blue, least=red
Water's dissolving power results from what?
polarity
Which wave length of the visible spectrum of light is most quickly absorbed in the top meter of the ocean?
red
Why does sound travel efficiently at minimum sound velocity in the Sofar Layer?
refraction
What is known about the minimum velocity layer?
solar layer (where sound travels slowly)
How does sound can travel through water compared to light?
sound travels faster in water than light before it is absorbed
cohesion is a property of water that gives water characteristic?
surface tension
The ocean is stratified by density, and is mainly a function of what?
temperature and salinity, it defines the different layers of the ocean.
What is water's latent heat of vaporization?
the amount of energy required to break hydrogen bonds (540 cal/g)
The relationship between the temperature (or salinity) of a substance and its density is represented by a curve based on what?
the density curve is based on the temp/salinity of a substance and its density at that point. Most substances behave where they become progressively more dense as they become cooler and their curve is linear. Water behaves differently.
What area of the ocean has the most pronounced thermocline?
tropics due to intense sun
The halocline is best described as:
where salinity increases rapidly
The thermocline is best described as:
where temperature decreases rapidly, the thermocline divides the upper mixed layer from the calm deep water below