Why sea water is salty

The seas and oceans have been and are objects of study by the scientific community. And it is that a large part of the biodiversity of the entire planet is found in these evils and a large amount of resources are extracted from them. However, there is a question that the entire community has always asked. Many people don't know Why sea water is salty.

For this reason, we are going to dedicate this article to telling you what are the main reasons why sea water is salty and how important this is for the development of life in these places.

Salt as a primary element

Salt is a mineral compound made up of various minerals. In fact, what we usually call "salt" is just one type of salt, but there are many types of mineral salts that can be found in nature. In this way, when we talk about salt, we refer to a compound, sodium chloride, which is a molecule made up of sodium and chlorine atoms.

When we find this salt in nature, we call it halite, which is the name for the mineral common salt. However, most of the salt that we find in our lives (especially in food) does not come from rock salt, but from sea salt. When seawater dries, only the liquid component, water, evaporates. Therefore, the rest of the solid components dissolved in the water are separated and in a solid state called saltpeter.

Saltpeter is mainly composed of table salt (sodium chloride), although it contains more minerals naturally dissolved in seawater. When salt is separated from the rest of the saltpeter, normal or table salt is obtained, that is, the salt that we use to flavor our food.

Why sea water is salty?

The answer is simple: for millions of years, rivers have deposited different mineral salts from the erosion of ocean rocks. Over time, the buildup of these sediments has resulted in an average salinity index, or salinity, of 3,5 percent in large amounts of seawater, or 35 grams of salt per liter of water.

The two main elements present in seawater are chlorine (1,9%) and sodium (1%)., which when combined create sodium chloride or table salt. In addition to the currents that flow into the sea, there are other phenomena that contribute to increasing salinity, such as the melting of ice, the evaporation of water, volcanic eruptions and hydrothermal vents.

In fact, you can find places on earth with salt. However, these are special places because most of the salt on our planet is concentrated in brine. This is due to the very simple fact that salt dissolves easily in water.

At the origin of our planet, all the salt was distributed in a similar way on the incandescent surface of the Earth. But as the surface cooled and Earth's water changed from gas to liquid, the first oceans formed. Then, the water cycle also begins. This water cycle means that ocean water it evaporates to form clouds, clouds produce rain, rain forms rivers, and finally rivers return the water to the sea, thus completing the cycle.

As we said, salt was initially distributed over the entire surface of the earth. When the water cycle begins, rainwater dissolves surface salt and is first absorbed by rivers, transferring it to the ocean. However, when seawater evaporates, the salt remains in the sea, so as the water cycle continues to repeat itself, the concentration of salt in the seawater is higher, and at the same time, the surface land descends little by little. Millions of years later, all the salt is carried away by the water, causing it to concentrate completely in the oceans of our planet.

Salt deposits on the earth's surface

In fact, natural deposits of salt can still be found in some places on the Earth's surface. This can be due to two different types of reasons. On the one hand, it may be a place where the water cycle failed to dissolve the original saltpeter deposits from the earliest times. In this way, they are mineral salts that have been in the same place since the birth of the earth.

On the other hand, you can find some equally salty valleys or inland seas. This is because the water cycle modifies the original salinity of the area. However, due to its topography, this area is not yet in contact and interconnected with the larger ocean. In this way, it is the amount of salt that cannot "escape" from those places, generally because it exists in remote areas of the mountains. Just as salt is concentrated in the ocean, it is also concentrated in the depressions or isolated valleys of some mountain systems, but in this case, despite millions of years, the salt cannot leave these enclaves since the water cycle began as it has passed. That's what happened at the Dead Sea, for example.

Some curiosities about why sea water is salty

If the salt from the ocean could be distributed on the Earth's surface, it would form a layer more than 152 meters thick. Rivers carry around 4 million tons of dissolved salt to the ocean.

Another question related to this topic is whether seawater is good for our health. Don't do this even if you're dying of thirst. Precisely because of its high concentration of salt, it is very harmful to the body.. What happens if you drink too much? Human cells have membranes that prevent free entry of salt, but they are semi-permeable, so it can easily enter the cell if it exceeds the allowed range. When extracellular salt is greater than intracellular salt, water moves out of the cell to maintain balance in a process called osmosis. When drinking seawater, the consequences of osmosis are catastrophic.

I hope that with this information you can learn more about why sea water is salty.