OCE1001 Ch 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.

What common household item is used in this video to demonstrate a technique used by oceanographers to measure seawater salinity?

a light bulb

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

Which of the following processes is responsible for the high surface salinities in regions with hot climates?

high rates of evaporation

As shown in the video demonstration, air has _____ electrical conductivity and a metal key has _____ electrical conductivity.

low; high

A group of two or more atoms held together by mutually shared electrons are called ________.

molecules

As demonstrated by the fluids shown in the video, the higher the salinity of a fluid, the __________ the light lit up.

more

Subatomic particles with a neutral charge are called ________.

neutrons

What are the two controlling factors that affect water density?

temperature and salinity

The states of matter in which water exists is primarily determined by:

temperature.

What is allowing electrical current to pass through tap water from one electrode to the other?

the amount of salt (dissolved substances)

In which fluid did the bulb shine the brightest?

the beaker filled with seawater

Of the three different colored waters separated by slats, which one has the highest density?

the cold (blue) water, which has the lowest temperature

Which of the following processes can provide fresh drinking water from seawater?

melting of icebergs distillation of evaporated seawater freeze separation of sea ice

How much more acidic is a substance with a pH of 2 than a substance with a pH of 5?

1000

The average salinity of typical seawater is:

3.5%.

Part B

45 grams

Part B

550 meters

Which of the following best describes the Electrolysis Method for desalination?

A current is run through positive and negative electrodes in freshwater separated by semipermeable membranes from seawater.

Part E

A: Greatest amount of evaporation (worldwide) B: Greatest amount of precipitation (worldwide) C: Smaller amount of precipitation (worldwide) D: Runoff E: Smaller amount of evaporation, including transpiration (worldwide) F: Infiltration

Part A

A: Hydrogen bond B: Oxygen atom C: Hydrogen atom D: Positively charged side of the water molecule E: Negatively charged side of the water molecule

Part C

A: Liquid B: Solid C: Gas

Part D

A: Sulfate B: Sodium C: Chloride D: Calcium E: Magnesium F: Potassium

Part F

A: Thermocline B: Mixed layer C: Layer with the highest density D: Curve for low latitudes E: Curve for high latitudes

Part B

A: Vaporization (evaporation/boiling) B: Melting C: Condensation D: Freezing

In the figure above, which shows water molecules. Which label(s) indicate a covalent bond?

B

On an annual basis which of the following fluxes between reservoirs of the hydrologic cycle is the smallest?

Continent to ocean

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.

Which of the following processes causes sea surface salinity to increase near the Tropics of Cancer and Capricorn?

Evaporation

Which process in the hydrologic cycle is most effective at increasing ocean salinity on a global scale?

Evaporation

Which statement accurately describes the thermostatic effect of water on climate moderation?

Evaporation in the tropics has a cooling effect on ocean temperature.

Part A

High temperature (does not change seawater salinity) Sea ice formation (increases seawater salinity. Precipitation (decreases seawater salinity.) River input (decreases seawater salinity.) Evaporation (increases seawater salinity.)

How do hydrogen bonds define the three states of matter in water?

Ice has more hydrogen bonds than water vapor does. There are no hydrogen bonds when water is in a gas phase. Water will be a solid if there are hydrogen bonds between all water molecules. In liquid water, there are some hydrogen bonds between water molecules that form and break repeatedly.

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.

Human consumption of which of the following components of seawater helps prevent goiter?

Iodine

What happened when a new (green) water mass was introduced into the system?

It came to equilibrium in the middle of the tank.

What makes water a polar molecule?

It has a positive hydrogen side and a negative oxygen side.

Which of the following statements is true of water in a solid state?

It is rigid and forms a three-dimensional crystalline shape. Water molecules in ice remain in a relatively fixed position and are not as mobile as they are in the liquid state, where there are fewer hydrogen bonds.

Part A

Locations that experience seasonal seawater freezing have (increased salinity) in the surrounding seawater during that time. Locations that experience seasonal ice melting have (decreased salinity) in the surrounding seawater during that time. Sample A: just East of the Bahamas Sample B: off the West coast of Africa, near the equator Sample C: from the Red Sea Sample D: from the Baltic Sea

On an annual basis which of the following fluxes between reservoirs of the hydrologic cycle is the largest?

Ocean to atmosphere

Which of the following best describes the Distillation Method for desalination?

Saltwater is boiled and the water vapor is passed through a cooling condenser, where it condenses as freshwater.

Which of the following best describes the Freeze Separation Method for desalination?

Seawater is frozen and thawed multiple times, with the salts washed from the ice between each thawing.

Part A

The state of matter in which water is densest (liquid) The state of matter in which water molecules are the most energetic (gas) The state of matter in which water is compressible (gas) The state of matter of steam rising from a hot cup of coffee (gas) The state of matter in which water molecules vibrate around fixed locations (solid) The state of matter of frost on grass (solid)

Which of the following best defines heat capacity?

The amount of heat energy required to raise the temperature of a substance by 1 degree Celsius.

What happened when the two slats were pulled out?

The blue water sank to the bottom and the red water rose to the top.

Of the following statements about the pH of seawater, which is/are true? Choose all that apply.

The carbonate buffering system stabilizes the pH of seawater. The pH of seawater is higher than that of pure water. Dissolving carbon dioxide in seawater decreases the pH of seawater.

Which of the following best defines temperature?

The direct measure of the average kinetic energy of a substance's molecules.

Why do ionic compounds dissolve readily in water?

The electrostatic attraction between ions is weakened by the polarity of water.

Which attributes of the water molecule arise from the unique bend in its geometry?

The hydrogen end has a positive charge, and the oxygen end has a negative charge.

Which statement accurately describes the interaction between a water molecule and sodium chloride as it dissolves?

The negative oxygen end of the water molecule is attracted to the positive sodium ion.

Of the following statements about seawater salinity, which is/are true? Choose all that apply.

The two most common dissolved components in seawater are sodium and chloride. Seawater salinity averages 3.5%. Seawater salinity averages 35 ppt.

Why are water molecules in a gas phase able to move rapidly and independently of each other?

There are no hydrogen bonds between water molecules in a gas phase, so each water molecule acts as an individual.

Of the following statements about seawater properties in high and low latitudes, which is/are true? Choose all that apply.

There is a thermocline in low latitudes. There is a halocline in low latitudes. There is a halocline in high latitudes. There is a pycnocline in low latitudes.

Of the following properties of water, which is/are caused by the unusual geometry of water molecules? Choose all that apply.

Water has the ability to dissolve just about anything. Water molecules form hydrogen bonds. Water has cohesion and surface tension. Water molecules have polarity.

Why does the water molecule have polarity?

Water is geometrically bent to give one side, or pole, a positive charge and the opposite side a negative charge.

Why is water able to dissolve salt?

Water molecules are polar and are attracted to the electrically charged ions that form salts.

Which of the following best describes the 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.

Of the following statements about the density of freshwater and the formation of ice, which is/are true? Choose all that apply.

Water's maximum density is at 4°C. Water at 2°C is less dense than it is at 4°C. Ice is less dense than liquid water, which is why ice floats. As the temperature of water decreases from 4°C to 0°C, its density decreases.

Which of the following statements is/are true of sea ice?

When sea ice forms, the water molecules preferentially exclude any salt in the water, resulting in ice that is mostly fresh. Sea ice formation increases the salinity of remaining seawater

The principal reason that oil and water do not mix, even when shaken, is that oil molecules __________.

are nonpolar whereas water molecules are polar

The basic building blocks of all matter are called ________.

atoms

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.

Subatomic particles with a negative charge are called ________.

electrons

If all the water in the ocean was evaporated and only the solid salt was left behind, how much salt would there be?

enough to form a layer about 500 feet thick that covers all of Earth

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 substances releases the most hydrogen ions when dissolved in water?

lemon juice

Which of the following statements is/are true regarding acidic and alkaline substances?

pH stands for "power of hydrogen." Blood, eggs, and seawater have a similar pH, adding support to the theory that life originally evolved in the ocean. pH is a measure of the concentration of hydrogen ions in a solution.

Which of the following processes decrease seawater salinity?

precipitation sea ice melting river runoff

Subatomic particles with a positive charge are called ________.

protons

In which of the following substances are there equal numbers of hydrogen ions and hydroxide ions?

pure water

A layer of rapidly changing density with depth is called a ________.

pycnocline

Which of the following processes increase seawater salinity?

sea ice formation evaporation

Which of the following substances releases the most hydroxide ions when dissolved in water?

sodium hydroxide

What common household item is used in this video to demonstrate how the ocean is layered based on density?

tap water, with a small amount of food coloring

Hydrogen bonds form between neighboring water molecules because of:

the polarity of water molecules.

A layer of rapidly changing temperature with depth is called a ________.

thermocline