Chemical Structure of Seawater

Seawater differs in chemical structure from plain water because of additional components that are present.  Just by tasting, you would know that seawater is briny and contains salts that are not found in your ordinary drinking water. What is the chemical structure of seawater that makes it different?

1. Seawater has salts

Seawater has an average salt content of approximately 35 grams for every    liter of seawater or 3.5% salt content.  The salt includes calcium (Ca++), potassium (K+), chloride (Cl-), sodium (Na+), sulfate (SO4++), and magnesium (Mg++). Sodium and chloride constitute majority of the seawater salts.

This chemical structure allows salinity of seawater. The salinity of seawater is constant and measuring one major salt allows representation of the other concentrations.

2. Seawater is denser than fresh water

The density of pure water is 1.00 grams per milliliter at specified temperatures. Seawater is denser, which is 1.025 grams per milliliter. The salt content of seawater makes it denser.

3. Seawater has a pH of 7.5 to 8.4

Pure water has a neutral pH at 7, but seawater is more alkaline with pH range of 7.5 to 8.4. This is due to the presence of additional chemical components not found in fresh water.  

4. Seawater has traces of other chemicals

Aside from the salts mentioned, seawater also has smaller amounts of strontium (Sr), bicarbonate (HCO3), bromide (Br), borate (BO3), and fluoride (F). There are still various chemicals present in sea water depending on its location and depth.

The aforementioned chemical structure of seawater enables measurement of distances based on sound which travels through the seawater’s components. These chemical components make seawater different from fresh water, pure water or river water.

The chemical components and salinity of water also prevents it from becoming potable or drinkable. The salt content of seawater could aggravate an existing condition of hypertension and cardiovascular conditions because the increased concentration of salt in the blood will influence the amount of water inside the cell. The increase of sodium will promote osmosis, which will eventually drain the cells of water. The dehydration of the cells can cause heart conditions like arrhythmia.

It is great to know the seawater’s chemical structure so that you will know why seawater is not advisable to drink and to hydrate the body with. Knowing this basic fact would also allow you to keep abreast of simple scientific information that are essential for your health and well-being.