Why is there so much salt in seawater, and where does it come from?

Because the surface of the ocean evaporates and turns into rain, it falls on the surface, which carries away water-soluble substances from rocks and soil, including many salts, so there is so much salt in the seawater. Although there is a lot of seawater, when we taste it, we feel that it is very salty, which means that it contains a lot of salt. And the salt we eat now is actually made from seawater.

All the water that exists on the earth is in a state of flux, and the water is subject to evaporation. Then the amount of water on the surface of the ocean will be evaporated, and when the water on the surface of the ocean is evaporated, it will become rain and fall on the surface. Rainwater carries away a lot of material as it passes through various rocks and soils, including a lot of salts.

When these substances are finally collected by the rain into the ocean, the salt on the ocean will increase, and the salt will not evaporate with the water, so it will be retained, and then after hundreds of millions of years of accumulation, the sea water will become as salty as it is now. <>

There are various elements in seawater, among which potassium, sodium, magnesium, calcium and other elements are the most abundant. If this type of element can be extracted from seawater, it is estimated that about 5.5 million tons, 13.7 billion aluminum, and 400 million tons of ** can be extracted. <>

Therefore, the ocean is very precious, and the value of the ocean for human beings is endless. Therefore, human beings should learn to protect the marine environment, understand environmental protection in daily life, and keep the marine ecology balanced, which is more beneficial to human beings.

The salt in the sea comes from the rocks that cover the earth. When the raindrops fall on the rocks, the rain dissolves some of the substances contained in the rocks, and slowly the water flows into the river and into the river, which flows into the sea, but the salt dissolved in the river water is very small, and after flowing to the sea, the seawater evaporates but the salt does not evaporate, so the salt of the seawater will be very large.

In fact, the sea water did not have salt in the beginning, but from the first rain on the earth, the rain washed away the rocks on the earth's surface, destroying the rock structure, and the minerals in the rocks would flow into the sea.

Most of the salt in the seawater is the salt from the soil on the land, which is brought into the sea by small rivers and rivers.

Why is there so much salt in seawater, and where does it come from?

Everyone knows that seawater is salty, this is because there is salt in seawater, so what about the salt in seawater? There are currently two theories on this issue.

One is that the sea water in the original ocean contained very little salt, even fresh water. Nowadays, most of the salt contained in seawater is the salt in the rocky soil on land, which is soaked and dissolved by rainwater, and flows into streams, rivers, and rivers into the ocean, and the water evaporates over time and the salt gradually accumulates. Some observations show that 3.9 billion tonnes of salt are now brought into the sea annually via rivers.

Therefore, some geologists calculate the age of the earth based on the amount of salt in the seawater.

Another is that the original sea water was salty. This is because the scientists who came up with this theory have observed changes in the salinity of seawater over a long period of time and found that the salinity in seawater does not increase over time. However, the amount and composition of salt contained in seawater varied throughout the period of the earth's development, and the reason for this change is still being explored.

How much salt is in seawater? According to the test, the average kilogram of seawater contains about 35 grams of salt. The main one is sodium chloride (table salt), which is due to the presence of a large amount of sodium chloride that gives seawater its salty taste; This is followed by magnesium chloride, magnesium sulfate (which is what we usually call Epsom salt), calcium sulfate, potassium sulfate, calcium carbonate and magnesium bromide.

They form the bitter taste of seawater.

Where does the salt in the sea come from?

Our country has a long coastline and many salt pans. The salt works along the coast produce a lot of salt every year. 1 kilogram of seawater contains about 35 grams of salt.

This salt is called sea salt. Among them, the salt used for seasoning is only 27 grams. The salt of seawater contains not only sodium chloride (table salt), but also magnesium chloride and other substances.

The sea is 2.4 times the size of the land, and according to rough calculations, the total salt content of the sea is 500 trillion tons. It is said that the salt content seems to be increasing.

So, where does the salt in the sea come from?

The salt in the sea comes from the rocks that cover the earth. Raindrops fall on the rocks, and the rain dissolves some of the substances contained in the rocks, and slowly the water (plus the spring water) turns into river water and flows into the sea.

However, when I scoop up the river water and taste it, I don't feel the saltiness at all.

This is because there is very little salt dissolved in the river water. When the river flows into the sea, there is nowhere to go. In this way, it seems that the sea will overflow at any moment.

No, it is said that the sea water is about 1 meter deep every year. The salt water of the river flows into the sea for many years, and the water in the sea evaporates year by year, and the amount of salt and other substances left in the sea increases year by year.

Why is there so much salt in seawater, and where does it come from?

The origin of salinity in seawater is a complex issue that is related to the origin of the earth and the formation and evolution of the oceans. It is generally believed that salt is mainly the product of crustal rock bloom and volcanic ejecta.

At first, scientists were convinced that seawater was intrinsic to the planet. They began to be stored in minerals and rocks in the form of structured water, crystalline water, etc. As the earth continues to evolve, they are released from minerals and rocks and become the first of the seawater.

However, some scientists disagree. They believe that this "nascent water" seeps in from the ground. In fact, all of these views are still speculation, and it is still far from truly unraveling the mystery of the earth's water sources.

With the development of ocean chemistry, people gradually understand seawater, and it is now determined that seawater contains more than 80 elements. But the levels of these elements in seawater vary greatly.

There are various salts dissolved in seawater, in addition to sodium chloride (the scientific name of salt), there are other chemical components such as magnesium chloride, magnesium carbonate, potassium, sodium, etc., nearly 100 kinds of salts of major and trace elements.

The main salt content of seawater is the weathering of crustal rocks and volcanic eruptions over billions of years. The surface rocks are washed and eroded by the current, and the salt in them is constantly dissolved in the water; These currents continue to merge into great rivers and rush into the sea.

Scientists have found that the world's rivers transport 5.5 billion hectares of dissolved salts to the ocean every year. As the water evaporates, the salt in the seawater gradually settles, and over time, the salt accumulates more and more, so that the seawater becomes salty. In addition, the eruption of an undersea volcano and the overflow of magma will also increase the salinity of the ocean. Quarrels.

Because seawater contains some salty substances. In fact, only the water in the seawater is occupied, and the rest is sodium chloride, magnesium chloride and other salts. The content of these salts in seawater is expressed in terms of salinity, which refers to the total amount of all dissolved substances in one kilogram of seawater, and the salinity of seawater is generally about 35 0 (i.e. 35 grams of salt in one kilogram of seawater).

Where does the salt in seawater come from? Volcanic eruptions, dust storms and rivers on land will bring large amounts of sodium, magnesium, calcium, sulfur, carbon, chlorine and other elements into the sea, and a considerable amount of salt elements will also be imported into the mid-ocean ridge of the seabed. Of course, if only salts are constantly entering the ocean, the sea will become saltier and thalitier (water vapor evaporation will not take away salts).

Fortunately, marine organisms absorb a lot of salts, and chemical adsorption and precipitation will also convert some salts in seawater into sediments. From the concentration of salt contained in the sediment, it can be inferred that the dissolved salts in the seawater remain in a stable state. Many of the salts in seawater are needed for the growth of marine organisms and are called nutrients (such as nitrates, silicates, phosphates, etc.).

Nutrient-rich seas often form good fishing grounds.