Wind Waves Salinity

Units for salinity are measured in

• parts per billion

• parts per thousand

• parts per billion

• parts per hundred

When the relative percentage of the major ions in seawater remains constant, even though the salinity may be different, it is called the

• relative salinity

• rule of constant proportions

• wave height

• ionization

The average salinity of the ocean is about

• 25 ppt

• 30 ppt

• 35 ppt

• 20 ppt

The saltier the water is, the denser it is.

• true

• false

The density of seawater depends on

• temperature

• salinity

• temperature and salinity

• temperature, salinity, and relative humidity

Metals and metalloids are often present in tiny amounts in the ocean. These are called

• trace elements

• ions

Which of the following is NOT a way in which trace elements usually enter the ocean?

• river runoff

• groundwater seeps

• hydrothermal activity

• human-derived inputs

• decaying organisms

Trace elements are NOT a source of nutrients for marine life.

• true

• false

Dissolved gases are an important part of the chemistry of seawater. What gas do marine plants and phytoplankton produce through photosynthesis?

• oxygen

• nitrogen

• carbon dioxide

• sulfur

Carbon dioxide is a natural gas that is removed from the atmosphere and dissolved into the ocean. Over time, the rate of CO₂ concentrations have increased drastically. Can our marine environment keep up with the rate of increase?

• yes

• no