Unique Nature of Pure Water
This common substance is the only one found naturally on Earth as a solid, liquid, and gas.
What is water?
Seawater is denser than freshwater mainly because it contains this.
What is dissolved salt?
The two most abundant ions in seawater
What are sodium and chloride?
This gas dissolves in seawater to form carbonic acid, lowering pH.
What is carbon dioxide (CO₂)?
The ocean plays this major role in the global carbon cycle
What is absorbing carbon dioxide from the atmosphere?
The type of bond that connects water molecules together.
What are hydrogen bonds?
The two main factors that control seawater density.
What are temperature and salinity?
Seawater has a pH around 8.1, meaning it is slightly this.
What is basic (or alkaline)?
As the ocean’s pH drops, it becomes this.
What is more acidic?
These microscopic ocean plants remove carbon dioxide through photosynthesis.
What are phytoplankton?
Ice floats because this property of water decreases when it freezes.
What is density?
This type of water — warm and less salty — tends to float on top of denser water.
What is surface water?
This system of carbonate and bicarbonate ions helps keep ocean pH stable.
What is the buffering system?
Ocean acidification harms coral reefs because it reduces the availability of this compound needed for shells.
What is calcium carbonate?
This process moves carbon from the atmosphere into the ocean when carbon dioxide gas dissolves into seawater.
What is gas exchange (or diffusion)?
These weak attractions constantly break and reform, giving water its fluid nature.
What are hydrogen bonds?
This property of seawater causes light to bend more than in freshwater.
What is refractive index?
These nutrients, such as nitrate and phosphate, are not evenly mixed and are more concentrated in deep water.
What are nutrients?
Over time, acidification impacts not just surface waters but also these deeper regions
What are deep ocean waters?
When marine organisms die, their carbon can stay trapped here for hundreds of years.
What is the deep ocean (or seafloor sediment)?
Pure water reaches its maximum density at this temperature.
What is 4 degrees Celsius?
This global circulation pattern is driven by differences in temperature and salinity.
What is thermohaline circulation?
This principle states that the relative proportions of major ions in seawater stay nearly constant everywhere.
What is the rule of constant proportions?
The most effective way to slow ocean acidification.
What is reducing carbon emissions?
Human activities like burning fossil fuels have disrupted this natural process.
What is the carbon cycle?