OCEAN ACIDIFICATION EXAM
QUESTIONS AND ANSWERS GRADED A+
2025/2026
The major components (from greatest to smallest component) of seawater are: -
ANS Hydrogen, Oxygen, Chlorine, Sodium, Magnesium, Sulfate, Calcium, Potassium
Other minor components are: - ANS Bromine, Boron, Carbon, Nitrogen, Strontium, Silicon
Some trace elements (found at less than 0.95ppm) include: - ANS Phosphorus, Argon, Zinc,
Rubidium
A carbon sink is, - ANS A natural or manmade reservoir that accumulates and stores some
carbon-containing chemical compound for an indefinite period.
The ocean is the - ANS largest natural carbon sink on Earth.
Carbon sequestration refers to - ANS the storage of carbon for indefinite time.
Carbon dioxide is taken up by - ANS marine plants and algae during photosynthesis.
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
, When carbon dioxide dissolves in seawater, - ANS most of it becomes bicarbonate ions and
hydrogen ions. This increase in hydrogen ions is what decreases the pH. In addition, some of the
hydrogen combines with carbonate to form more bicarbonate, decreasing the concentration of
carbonate in seawater. Many marine organisms use carbonate, combined with calcium, to form
their exoskeletons, shells or other structures (e.g. corals).
Carbon dioxide in the atmosphere has been increasing since industrial times because of -
ANS use of energy in homes, burning of fossil fuels for industry, emissions from
transportation, cement manufacturing and deforestation.
Increased acidity can lead to - ANS coral reef decline
How can ocean acidification affect marine life? - ANS Breaking down exoskeletons and shells.
Evidence shows that some shelled organisms build shells more slowly, and some shells weaken
and dissolve in acidic environments.
As you know, CO2 from the atmosphere dissolves into seawater. Let's look at this process in
more detail: - ANS First, CO2 reacts with water to form carbonic acid (H2CO3-):
(1) CO2 + H2O > H2CO3-
Carbonic acid can then dissociate into bicarbonate (HCO3-):
(2) H2CO3- > H+ + HCO3-
Bicarbonate can then dissociate into carbonate ions (CO32-)
(3) HCO3- > H+ + CO32-
list two examples of vital uses of calcium carbonate to marine life? - ANS Shell formation,
exoskeleton formation, coral reef formation
2 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS GRADED A+
2025/2026
The major components (from greatest to smallest component) of seawater are: -
ANS Hydrogen, Oxygen, Chlorine, Sodium, Magnesium, Sulfate, Calcium, Potassium
Other minor components are: - ANS Bromine, Boron, Carbon, Nitrogen, Strontium, Silicon
Some trace elements (found at less than 0.95ppm) include: - ANS Phosphorus, Argon, Zinc,
Rubidium
A carbon sink is, - ANS A natural or manmade reservoir that accumulates and stores some
carbon-containing chemical compound for an indefinite period.
The ocean is the - ANS largest natural carbon sink on Earth.
Carbon sequestration refers to - ANS the storage of carbon for indefinite time.
Carbon dioxide is taken up by - ANS marine plants and algae during photosynthesis.
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
, When carbon dioxide dissolves in seawater, - ANS most of it becomes bicarbonate ions and
hydrogen ions. This increase in hydrogen ions is what decreases the pH. In addition, some of the
hydrogen combines with carbonate to form more bicarbonate, decreasing the concentration of
carbonate in seawater. Many marine organisms use carbonate, combined with calcium, to form
their exoskeletons, shells or other structures (e.g. corals).
Carbon dioxide in the atmosphere has been increasing since industrial times because of -
ANS use of energy in homes, burning of fossil fuels for industry, emissions from
transportation, cement manufacturing and deforestation.
Increased acidity can lead to - ANS coral reef decline
How can ocean acidification affect marine life? - ANS Breaking down exoskeletons and shells.
Evidence shows that some shelled organisms build shells more slowly, and some shells weaken
and dissolve in acidic environments.
As you know, CO2 from the atmosphere dissolves into seawater. Let's look at this process in
more detail: - ANS First, CO2 reacts with water to form carbonic acid (H2CO3-):
(1) CO2 + H2O > H2CO3-
Carbonic acid can then dissociate into bicarbonate (HCO3-):
(2) H2CO3- > H+ + HCO3-
Bicarbonate can then dissociate into carbonate ions (CO32-)
(3) HCO3- > H+ + CO32-
list two examples of vital uses of calcium carbonate to marine life? - ANS Shell formation,
exoskeleton formation, coral reef formation
2 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
