01
True or false
1 point
Wind and waves mix the upper ocean, making properties in the surface mixed layer relatively uniform.
Free Practice Quiz Question List
3 Seawater Properties Online Quiz Questions
Use this free practice quiz with 20 questions to review 3 Seawater Properties, test your knowledge, and prepare for your next test or exam.
20 questions
02
True or false
1 point
The deep layer has the same temperature and other properties in every ocean region.
- A
True
- B
False
03
Fill in the blank
1 point
When evaporation removes water from seawater but leaves its salts behind, salinity tends to .
04
Choose one
1 point
Sea ice forms beside a parcel of seawater. What is the likely effect on the salinity of the nearby seawater?
- A
Nearby seawater becomes less salty because the ice removes salt from it.
- B
Nearby seawater remains unchanged because ice formation does not affect salt distribution.
- C
Nearby seawater becomes saltier because much of the salt is excluded from the ice.
- D
Nearby seawater becomes saltier because the ice releases freshwater into it.
05
Choose one
1 point
Ocean water shows a strong, rapid change in density over a short vertical distance. What is this zone called?
- A
A zone of rapid temperature change
- B
A zone of rapid density change
- C
A zone of rapid salinity change
- D
A wind-mixed layer with relatively uniform properties
06
True or false
1 point
Under typical conditions, tropical surface seawater is generally warmer than surface seawater near polar regions.
- A
True
- B
False
07
Fill in the blank
1 point
Complete each definition: A zone of rapid temperature change with depth is a ; a zone of rapid salinity change with depth is a .
08
Written response
1 point
About what percentage of seawater by mass is water? Enter the percentage value only.
09
Choose all
1 point
Which changes generally increase seawater density? Select all correct choices.
- A
Increasing salinity increases density.
- B
Increasing temperature increases density.
- C
Decreasing temperature increases density.
- D
Increasing pressure slightly increases density.
10
Choose all
1 point
Which statements describe ways that seasonal conditions or surface freshwater can affect ocean layering? Select all correct choices.
- A
Seasonal heating can strengthen surface layering.
- B
Winter cooling and stronger mixing can weaken surface layering.
- C
Seasonal heating always eliminates ocean layers.
- D
Freshwater entering at the surface can form a less-salty layer above denser water.
11
Written response
1 point
What is the approximate average open-ocean salinity, expressed as grams of salts per kilogram of seawater?
12
Open ended
1 point
Why does seawater freeze at a lower temperature than freshwater?
13
Choose one
1 point
Which pair consists of the most abundant dissolved ions in seawater?
- A
Sulfate and magnesium
- B
Chloride and sodium
- C
Calcium and potassium
- D
Nutrients and dissolved gases
14
Written response
1 point
Average open-ocean salinity is about 35‰. Express this value as a percentage. Enter the numeric value in percentage points.
15
Choose one
1 point
A seawater profile shows a sharp temperature change over a small increase in depth. What is this zone called?
- A
A zone of rapid salinity change with depth
- B
A layer where winds make temperature uniform
- C
A zone of rapid temperature change with depth
- D
A zone of rapid pressure change with depth
16
Written response
1 point
What process raises salinity when water is removed from seawater but its dissolved salts remain?
17
Choose one
1 point
What is the general effect of rainfall or river inflow on ocean surface salinity?
- A
Surface salinity generally increases because freshwater adds dissolved salts.
- B
Surface salinity generally decreases because freshwater dilutes the seawater.
- C
Surface salinity remains unchanged because freshwater has no effect on seawater.
- D
Surface salinity decreases only when the water temperature rises.
18
Choose one
1 point
Which statement best describes how increasing pressure affects seawater density as depth increases?
- A
It lowers density because deeper water is colder.
- B
It has no effect on density at any depth.
- C
It increases salinity and therefore greatly increases density.
- D
It slightly increases density as pressure rises with depth.
19
Choose one
1 point
Two nearby parcels are otherwise under similar conditions: one is warm and relatively fresh, and the other is cold and salty. Which outcome is most likely before significant mixing occurs?
- A
The warm, fresh parcel tends to sink because it contains more water.
- B
The cold, salty parcel tends to sink because it is generally denser.
- C
Both parcels must remain at the same depth because temperature and salinity cancel.
- D
The cold, salty parcel tends to rise because salt makes seawater less dense.
20
Choose one
1 point
Which statement best describes how seasonal heating and winter conditions can affect ocean surface layering?
- A
Seasonal heating can strengthen surface layering, while winter cooling and stronger mixing can weaken it.
- B
Winter cooling always strengthens layering because cold water is denser.
- C
Seasonal heating and winter cooling have no influence on layering.
- D
Winter cooling strengthens layering only by increasing surface salinity.