Section 13B

The ocean’s saltiness is its __

Typical ocean salinity is ___ %

• 25

• 35

• 3.5

• 2.5

The most common dissolved gas found in seawater is ___

• carbon dioxide

• oxygen

• nitrogen

• argon

Processes that increase the salinity in the ocean are __

• evaporation of seawater (high temperature

• Run off of minerals

• Settling of volcanic ash

• Hydrothermal vents

• Animals such as coral/seashells that use chemicals from the ocean to make their shells/skeletons

Processes that decrease the salinity in the ocean are: 

• Run off of minerals

• Animals such as coral/seashells that use chemicals from the ocean to make their shells/skeletons

• Hydrothermal vents

• Mineral ions suspend in clumps and sink to the bottom of the ocean (when they become heavy enough)

• The chemicals (salt) can become so concentrated that they precipitate and settle at the bottom of the ocean.

Water that has low salinity is called ___ water (it is usually at the mouth of a river).

When ocean water freezes, the salts settle out of the ice, causing the remaining water to be ___ in salinity.

• higher

• lower

• the exact same

Surface temperatures of the ocean vary significantly from the equator (lots of sun) to the poles (little sunlight); however below a depth of 1,000 ft the ocean temperature is relatively ___.

While fresh water freezes at 0o C, saltwater freezes at ___ degrees C

• 1.8

• 3.5

• -3.5

• -1.8

Seawater increases at a pressure of one atmosphere every ___ meters you descend

• 100

• 10

• 1

• 1,000