Science, Tech, Math › Science What Is the Most Abundant Salt in the Ocean? Share Flipboard Email Print Young girl in the Dead Sea holding sea salt, En Bokek, Israel. Getty Images/Elan Fleisher/LOOK-foto Science Chemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 30, 2019 There are several salts in seawater, but the most abundant is ordinary table salt or sodium chloride (NaCl). Sodium chloride, like other salts, dissolves in water into its ions, so this is really a question about which ions are present in the greatest concentration. Sodium chloride dissociates into Na+ and Cl- ions. The total amount of all types of salt in the sea averages about 35 parts per thousand (each liter of seawater contains about 35 grams of salt). Sodium and chloride ions are present at much higher levels than components of any other salt. Chemical Concentration (mol/kg) H2O 53.6 Cl- 0.546 Na+ 0.469 Mg2+ 0.0528 SO42- 0.0282 Ca2+ 0.0103 K+ 0.0102 C (inorganic) 0.00206 Br- 0.000844 B 0.000416 Sr2+ 0.000091 F- 0.000068 Molar Composition of Seawater Reference: DOE (1994). In A.G. Dickson & C. Goyet. Handbook of methods for the analysis of the various parameters of the carbon dioxide system in sea water. 2. ORNL/CDIAC-74. What Is a Hypertonic Solution? Why Is the Ocean Salty? Sodium Chloride: The Molecular Formula of Table Salt How Salty Is the Ocean? Salinity: Definition and Importance to Marine Life Is Dissolving Salt in Water a Chemical Change or Physical Change? Common-Ion Effect Definition How Salt Forms in Nature Why Does Salt Melt Ice? Science of How It Works How to Make Potassium Nitrate The Difference Between Sodium and Salt Salt Definition in Chemistry Freezing Point Depression Why Adding Salt to Water Increases the Boiling Point What Is Table Salt? Why Is Water the Universal Solvent?