Reef Chemistry Question of the Day #95 Surface Ocean Depletion

Randy Holmes-Farley

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Reef Chemistry Question of the Day #95

The surface waters of the ocean often get depleted in certain ions due to the scavenging by organisms that need those ions to thrive.

Which of the following ions is not depleted in surface ocean water?

A. Phosphate
B. Potassium
C. Silicate
D. Nitrate
E. Chromium
F. Iron

Good luck!





















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tonizzy22

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Answer is B Potassium There is so much of it in sea water but it is hardly used and all other elements are in very small quantities.
 

Cory

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e chromium. Phytoplankton consume all the others. However potassium sounds plausible too.
 
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Randy Holmes-Farley

Randy Holmes-Farley

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And the answer is...B. Potassium

There is so much potassium in seawater that even though organisms generally accumulate it in their bodies relative to the same volume of seawater, they do not deplete it significantly. Consequently, the only way that potassium varies in the oceans is by changes in salinity, ior near local sources such as rivers or volcanic vents that may have more.

All of the other ions are also taken up and used by organisms, but there is naturally so much less of these that the levels in the ocean get depleted in places with a lot of life, such as the near surface region of the ocean.
 

Cory

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They told me in school to always pick your first answer! Liars! :D
 

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