There is more to seawater than H2O and sodium chloride.
Facts surrounding seawater are fascinating. The water of our oceans is often called saltwater due to the large percentage of dissolved salts found there. By far the most common salt is sodium chloride, but other compounds are also present. The salinity of saltwater varies around the globe, with the lowest concentrations found near the two poles, and the densest solutions occurring near the equator. Seventy-one percent of the Earth's surface is covered by oceans, and saltwater accounts for 99 percent of the world's water reserve.
Most Common Elements
The most common elements of seawater occur in water and salt. Water, also known as hydrogen oxide, contains hydrogen and oxygen. Alternatively, "salt" is a general term for a substance that is created by mixing an acidic and basic compound. More specifically, acid-base reactions create a positive cation, or positively charged ion, and a negative anion, or negatively charged ion, which after combining to form a new substance are precipitated in the form of a solid salt. In seawater, sodium chloride is by far the most common salt, but other positive ions such as magnesium, potassium and calcium are present along with the negative ion of sulfate (SO4). These ions can form in various combinations to create other types of salts. Other less common ions might consist of borate (BO3), fluoride, strontium, bromide and bicarbonate (HCO3).
Dissolved Gases
Several dissolved gases are present in seawater. These are oxygen (O2), carbon dioxide (CO2), nitrogen and argon. When in the gaseous state, oxygen and carbon dioxide are available for use by both plant and animal life. Oxygen is vital for respiration in animals, while photosynthesis cannot take place in green plants without the presence of carbon dioxide. Oxygen can be utilized by animal life only when it bonds with another oxygen atom to form a gaseous molecule, which is chemically expressed as O2. Carbon dioxide occurs when two atoms of oxygen bond to one atom of carbon.
Trace elements
Every natural element known to man has a presence in the planet's seawater. This even includes rare metals such as gold, silver, platinum and titanium. Nonetheless, these elements occur in such minute quantities that mining the ocean water for precious elements is not economically feasible. Outside of water and the basic salts and organic compounds, the most common elements in seawater are silicon, phosphorous, lithium, rubidium, iodine and barium.
Carbon
The carbon cycle produces many kinds of compounds that find their way into seawater. Of course, the element carbon is the major part of this chain, and it is released into the aquatic environment in a variety of ways. Excretion produces numerous complex carbon compounds along with many nitrates. Decay of living material is also another biological mechanism that adds carbon material to the seven seas. Additionally occurring are the secretion of various proteins and pheromones, which although small still adds some carbon-based material. And last but not least is the exchange of gases among living organisms, in which carbon dioxide is an integral part.
Tags: carbon dioxide, sodium chloride, along with, animal life, common elements, common elements seawater, common salt
