More elements will likely be found in the
future as measuring techniques improve through advances in technology.
Besides the water itself (H2O), here is a list of the principal chemical constituents in seawater, with their chemical symbol, and their relative The diagram at the upper left shows the principal
constituents and their concentrations in a sample of sea water with a salinity of 3.5% or 35 o/oo (parts per thousand).
Chloride ion (Cl-) -- 55%
Sodium (Na+) -- 30.6%
Sulfate (SO4-2) -- 7.7%
Magnesium (Mg +2) -- 3.7%
Calcium (Ca+2) -- 1.2%
Potassium (K+) - 1.1%
And a small amount (0.7%) of other stuff..........
Oceanographers report salinity
(total salt content) and the concentrations of individual
chemical constituents in sea water in parts
per thousand (also called parts per mil), for which the
symbol o/oo is used.
Remember that % is the symbol for percent
or parts per hundred -- divide % by ten or add another zero in the denominator
and you have parts per thousand.
Thus, a salinity value of 35o/oo
means 35 parts of dissolved salt per 1,000 parts of sea water. Similarly,
a sodium (Na+) concentration of 10 o/oo means
10 pounds of sodium per 1,000 pounds of water.