The removal of ions and molecules from sea water through adherence to a clay particle is termed:
Which of the following statements on ocean salinity is not correct?
|A)||Average salinity is 35 percent.|
|B)||There are, on average, 35g of dissolved salt in every kg of seawater.|
|C)||Salinity of ocean surface water is associated with latitude.|
|D)||Salinities will be lower in areas of high precipitation.|
Select the ion which is not a major constituent of seawater.
Which of the following is not a trace element in sea water?
Which of the following is not a mechanism for regulating the ocean's salt balance?
|C)||hydrothermal vent activity|
|D)||All of the above are mechanisms.|
Which of the following statements on the abundance of salts is not correct?
|A)||The average time that a substance remains in solution is measured by its half-life.|
|B)||Aluminum remains in solution for only short periods of time relative to other ions.|
|C)||Sodium is very soluble and will remain in solution for very long periods of time.|
|D)||Calcium is removed quickly from solution to form shells for organisms.|
The principle of constant proportion:
|A)||applies to only the trace elements.|
|B)||can only be applied near river mouths.|
|C)||states that the ratio of major ions does not change with salinity.|
|D)||is different at the ocean bottom than on the surface.|
The following method is not used to accurately determine the salinity of seawater.
Which of the following describes the saturation values of a gas?
|A)||Temperature, salinity, and pressure do not affect saturation value.|
|B)||If the temperature increases, the saturation value increases.|
|C)||As pressure increases, saturation value decreases.|
|D)||Decreasing the temperature increases the saturation value.|
The depth that represents equilibrium between oxygen and carbon dioxide production is termed the ____________ depth.
Which of the following statements about the distribution of gases is not correct?
|A)||Plants produce oxygen through photosynthesis at all depths.|
|B)||Oxygen values of quiet surface waters may become supersaturated.|
|C)||Anoxic conditions may occur on the floor of deep basins.|
|D)||Carbon dioxide levels at the surface are typically very low because of photosynthesis.|
The concentration of this ion determines the pH of water.
Carbon dioxide and water combine to form:
Research on ice cores recovered in Greenland and Antarctica have revealed all but which of the following?
|A)||Carbon dioxide concentrations in the atmosphere dropped rapidly at the end of the last ice age.|
|B)||Volcanic dust trapped in the ice reveals when and where eruptions occurred.|
|C)||Pollution from the ancient Greeks and Romans reached Greenland.|
|D)||Climate changes may occur very rapidly.|
The rate at which the oceans absorb CO2 is controlled by all but which of the following?
|A)||presence of calcium and carbonate ions|
|B)||transfer of carbon from CO2 to organic molecules|
|C)||circulation of deep ocean water|
|D)||presence of oxygen|
Carbon dioxide is not released by which of the following?
|A)||burning of fossil fuels|
|B)||decay of organic material|
|C)||respiration of organisms|
|D)||production of calcium carbonate by organisms|
Which of the following statements regarding salt sources is not correct?
|A)||Water carrying sulfate ions is acidic and helps liberate cations in bedrock.|
|B)||The chemical composition of most rivers mirrors that of the oceans.|
|C)||Water emerging from a hydrothermal vent is more saline than water entering the hydrothermal system.|
|D)||There are large quantities of cations in volcanic rocks.|
Select the following statement that does not accurately discuss chemical resources of the oceans.
|A)||Less than 50 percent of the world's table salt is extracted from seawater.|
|B)||Uranium and gold have been found to be economically feasible to extract from ocean water.|
|C)||Sea salt can be extracted in cold climate ponds by freezing sea water to a concentrated brine.|
|D)||The majority of the world's supply of magnesium comes from the sea.|
Which of the following statements on desalination is not correct?
|A)||Solar powered stills can produce fresh water, but at a very slow rate.|
|B)||Distillation through boiling water and capturing condensate is energy intensive and expensive.|
|C)||Low salinity water can be desalinated by ion exchange.|
|D)||Solar evaporation does not work because the salt evaporates with the water.|
The process of reverse osmosis in desalination:
|A)||is more energy intensive than the evaporative processes.|
|B)||is powered by the natural movement of water from high salinity to low salinity.|
|C)||produces no brines to be disposed of.|
|D)||is replacing older distillation plants in water poor areas.|
Which of the following is an example of a cation?
Which is not true about the latitudinal variations in seawater salinity?
|A)||Surface salinity is lower near the equator where precipitation exceeds evaporation.|
|B)||Surface salinity is high near 30oN and 30oS where evaporation exceeds precipitation.|
|C)||Salinity is high at the poles where evaporation is low.|
|D)||Salinity is low in the mid latitudes (60oN and 60oS) where precipitation exceeds evaporation.|
Arrange the following constituents in seawater in order from highest to lowest concentration:
|A)||magnesium, sodium, potassium, chloride, sulfate|
|B)||chloride, sodium, sulfate, magnesium, calcium, potassium|
|C)||chloride, sodium, calcium, potassium, magnesium, sulfate|
|D)||magnesium, sodium, calcium, potassium, sulfate|
Which of the following is not a process that adds salt to the ocean?
|A)||hydrothermal activities at mid ocean ridges|
Which of the following ions has the greatest residence time in the oceans?
Which of the following substance has the lowest pH?