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Which ions make up about 99 percent of the salts dissolved in seawater?
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seawater
Clear ocean water near a beach on Grand Bahama Island in The Bahamas.
The six most abundant ions in seawater, which together constitute approximately 99 percent of all dissolved sea salts by weight, are:
These major constituents maintain remarkably constant relative concentrations throughout the world's oceans, allowing oceanographers to calculate their levels based on salinity measurements.12