Question

ocean water and the air constantly exchange gases. co₂ can enter ocean water directly from the atmosphere. after dissolving in water, co₂ may either be absorbed by organisms or sink deeper into the ocean. carbon in the deep ocean may be stored as sediments on the seafloor. over time, carbon in the deep ocean is cycled back to the surface as the water circulates. co₂ at the oceans surface can move back into the air. but taken altogether, ocean activities are a net carbon sink. select the true statements. all of the co₂ at the oceans surface sinks deeper into the ocean. co₂ from the atmosphere is absorbed by both ocean water and plants. co₂ is constantly exchanged between the atmosphere and the ocean. overall, the ocean absorbs more carbon than it releases.

Explanation:

• For "All of the CO₂ at the ocean’s surface sinks deeper into the ocean": The text says CO₂ at the surface can move back into the air, so this is false.
• For "CO₂ from the atmosphere is absorbed by both ocean water and plants": The text states CO₂ enters ocean water and can be absorbed by organisms (which include plants), so this is true.
• For "CO₂ is constantly exchanged between the atmosphere and the ocean": The text says ocean water and air constantly exchange gases, so this is true.
• For "Overall, the ocean absorbs more carbon than it releases": The text says ocean activities are a net carbon sink (absorbs more than releases), so this is true.

Answer:

B. $\ce{CO_{2}}$ from the atmosphere is absorbed by both ocean water and plants.
C. $\ce{CO_{2}}$ is constantly exchanged between the atmosphere and the ocean.
D. Overall, the ocean absorbs more carbon than it releases.