How carbon moves
1 min 41 s. The words are spoken and shown in the picture; the player can also show them as subtitles.
For the Earth and Space Sciences Regents. Topic: Carbon cycling, with the past questions on it.
What Dr. Mars says (the words of the video)
Where does the carbon in the air go?
Carbon moves between air, water, living things and rock.
Atmosphere, hydrosphere, biosphere and geosphere.
Plants take carbon dioxide from the air by photosynthesis.
Respiration returns it to the air.
Carbon dioxide dissolves in rain water and in the ocean.
Sea animals use dissolved carbon to build calcium carbonate shells.
The shells settle and slowly become limestone.
Dr. Mars puts a drop of dilute hydrochloric acid on limestone.
It fizzes. The bubbles are carbon dioxide from the rock: limestone stores carbon.
Volcanoes return carbon from rock to the air, slowly.
This is part of the slow carbon cycle.
Burning coal, oil and gas moves carbon stored in rock to the air fast.
Fossil fuels are carbon stored in rock.
Check yourself! Which arrow moves carbon stored in rock to the air fastest: A, B, or C?
Think about where each arrow starts, and how fast.
Answer: B! Burning fossil fuels moves it to the air fast.
Dr. Mars's acid test showed that rock stores carbon.
Dr. Mars. Free practice for the New York Earth and Space Sciences Regents.