OCE CHAPTER 5
Which of the following is not one of the reasons why water is considered a universal solvent?
When the ions separate, they become attracted to identically charged water molecules.
We would expect the salinity of surface waters to be higher in regions where __________.
evaporation is much greater than precipitation
Which of the following occurs at the same temperature as the melting point?
freezing point
A layer of rapidly changing salinity with depth is called a
halocline
Which property of water causes coastal communities to have only moderate differences in daily highs and lows when compared to inland communities?
high heat capacity
A group of two or more atoms held together by mutually shared electrons are called ________.
molecules
Electrons
negatively charged subatomic particles that orbit an atomic nucleus
On an annual basis which of the following fluxes between reservoirs of the hydrologic cycle is the largest?
ocean to atmosphere
We might expect to encounter brackish ocean surface water
off the coast of Washington and Oregon
The primary difficulty that must be overcome in the use of desalination plants to provide fresh water is
the high cost of energy involved
This diagram shows how seawater temperature varies with depth. Match the correct letter to the items indicated below.
1. D: Curve for low latitudes 2. C: Layer with the highest density 3. A: Thermocline 4. B: Mixed layer 5. E: Curve for high latitudes
The diagram below shows selected components of the hydrologic cycle. Match the correct letter to each process (arrow) indicated.
1. A: Greatest amount of evaporation (worldwide) 2. C: Smaller amount of precipitation (worldwide) 3. D: Runoff 4. E: Smaller amount of evaporation, including transpiration (worldwide) 5. F: Infiltration 6. B: Greatest amount of precipitation (worldwide)
The image below depicts water in the three states of matter. Match the processes involved as water changes state with the correct letter.
1. A: Vaporization (evaporation/boiling) 2. C: Condensation 3. D: Freezing 4. B: Melting
Match the correct letter to each of the states of water listed below.
1. C: Gas 2. A: Liquid 3. B: Solid
The image below depicts several water molecules. Match the correct letter to each of the following features.
1. D: Positively charged side of the water molecule 2. E: Negatively charged side of the water molecule 3. A: Hydrogen bond 4. C: Hydrogen atom 5. B: Oxygen atom
On the lower pie diagram shown below, match the abundance of each dissolved component in seawater with its correct slice of the pie.
1. F: Potassium 2. E: Magnesium 3. A: Sulfate 4. B: Sodium 5. C: Chloride 6. D: Calcium
Part C - Dynamics of ocean density
1. Water expands when it is heated, making the density decrease. 2. Water that is isothermal will be represented by a straight line on a graph showing variations in temperature with depth. 3. The Sun penetrates surface waters enough at low latitudes to create a thermocline. 4. We expect a water column to be isopycnal for density at high latitudes. 5. In lower latitudes where a thermocline exists, as we drop down from the surface through ocean water, water density will increase while water temperature will respond inversely. 6. Both the thermocline and pycnocline present a barrier to mixing between near surface waters and deep ocean depths.
Sea surface salinity is greatest at which of the following latitudes?
25 degrees
The average salinity of typical seawater is:
3.5%
Imagine you are swimming in the open ocean at a location near the equator. Based on the following data, can you determine how deep you would need to dive to reach a water temperature of 19°C?
550 meters
Electrolysis Method for desalination
A current is run through positive and negative electrodes in freshwater separated by semipermeable membranes from seawater.
pycnocline
A layer in the ocean where a rapid change in ocean density occurs with a change in depth is called
Which of the following hydrologic cycle reservoirs is the smallest?
Atmospheric water vapor
Which of the following properties of pure water is different depending on the amount of water present?
Color
There is a general trend of decreasing pH with increasing water depth in the ocean. What is the cause of this pattern?
Deeper, colder ocean water contains more dissolved carbon dioxide, which causes the pH to be lower.
Of all the following processes which one increases the salinity of water?
Evaporation
Which of the following processes causes sea surface salinity to increase near the Tropics of Cancer and Capricorn?
Evaporation
PART A - Relationship between ocean temperature and density
From LEFT to RIGHT density, temperature thermocline water temperature..., inversely related, water at maximum density
The ion in sea water that serves as a buffer is
HCO3-
Which of the following surface seawater salinity conditions would you predict for the following location: Latitude: 20°N Longitude: 180°W
High surface seawater salinity due to evaporation
Which of the following statements regarding water density is correct?
Increasing the pressure decreases the temperature of maximum density for freshwater because the formation of bulky ice crystals is inhibited.
A beaker contains a mixture of ice and pure liquid water at 0oC. What happens to the temperature of the liquid water as heat is added?
It remains constant until the ice melts, and then it begins to rise.
Which of the following techniques can be used to measure the salinity of seawater? Choose all that apply.
Measure the chlorinity of the water. Evaporate the water sample and weigh the amount of solids that precipitate out. Pass electrical current through the water.
Of the following statements about the density of seawater, which is/are true?
NOT: A decrease in salinity increases seawater density. An increase in temperature increases seawater density.
Of the following statements about water's latent heat and changes in state, which is/are true? Choose all that apply.
NOT: In all three states of matter, there are no strong (covalent) bonds.
Part B - Water density case study Select the three statements below that apply.
NOT: Isopycnal means the samples of the water column have constant temperature throughout its depth.
Of the following properties of water, which is/are caused by the unusual geometry of water molecules? Choose all that apply.
NOT: Water density is greatest when solid.
The low pH layer in the ocean is due to which of the following processes?
Respiration
Distillation Method for desalination?
Saltwater is boiled and the water vapor is passed through a cooling condenser, where it condenses as freshwater.
Freeze Separation Method for desalination
Seawater is frozen and thawed multiple times, with the salts washed from the ice between each thawing.
Of the following statements about seawater salinity, which is/are true? Choose all that apply.
Seawater salinity averages 3.5%. Seawater salinity averages 35 ppt. The two most common dissolved components in seawater are sodium and chloride.
Which of the following is an application of the principle of constant proportions?
The concentration of a single major constituent can be measured to determine the total salinity of a water sample.
Which of the following best defines heat?
The energy transfer from one body to another due to a difference in temperature.
Reverse Osmosis Method for desalination?
Water on the salty side of a semipermeable membrane is pushed under high pressure through the membrane to the freshwater side.
The depth at which calcite dissolves rapidly in the ocean is called the __________.
alcite compensation depth or CCD
As a whole, the pH of surface waters of the ocean is slightly __________.
alkaline
Pycnocline
area of rapid change in density with slight change in depth
thermocline
area of rapid change in ocean temperature with a slight change in depth
Halocline
area of rapid change in salinity with slight change in depth
Atoms
basic building blocks of all matter
Hydrogen Bonds
bonds that hold adjacent water molecules together
Covalent Bonds
bonds that involve the sharing of electrons between atoms
Carbon dioxide (CO2) combines with water (H2O) to form __________.
carbonic acid (H2CO3)
Condensation
change in state from gas to liquid
Evaporation
change in state from liquid to gas
Sublimation
change in state from solid to gas
Ions
charged atoms due to the gain or loss of one or more electrons
If you were an explorer stranded in the Arctic Ocean, what method(s) could you use for creating fresh drinking water? Choose all that apply.
check everything except for "melt recently frozen seawater".
Which is the most abundant ion in seawater?
chloride
Calcite-secreting organisms such as __________ and __________ live in the ocean's sunlit surface waters and form the basis of most marine food webs.
coccolithophores; foraminifers
The density curve for high latitudes shows ________ density at the surface and ________ density at depth.
decreased, increased
As the salinity of seawater increases, its:
density increases
All the following processes decrease seawater salinity except :
evaporation
The pH scale is a measure of the __________ ion concentration of a solution.
hydrogen
The salinity curve for low latitudes shows ________ salinity at the surface and ________ salinity at depth.
increased, decreased
Atoms that have lost or gained one or more electrons are called ________.
ions
The surface tension of water:
is relatively high
Which of the following methods cannot be used to desalinate water?
osmosis
Which of the following statements regarding pH is true?
pH relates to relative acid-base ion balance in a solution.
Which of the following is the second most abundant negatively charged component of seawater?
sulfate
The states of matter in which water exists is primarily determined by:
temperature
Hydrogen bonds form between neighboring water molecules because of:
the polarity of water molecules.
The Principle of Constant Proportions states that:
the relative concentrations of the major ions in seawater does not change.
Salinity at different locations
top to bottom: increased salinity decreased salinity just east of the bahamas off the west coast of Africa from the Red Sea from the Baltic Sea
