Seawater is the "hometown" of salt, which contains all kinds of salt, about 90% of which is sodium chloride, that is, salt. In addition, it also contains magnesium chloride, magnesium sulfate, magnesium carbonate and other salts containing potassium, iodine, sodium, bromine and other elements. Magnesium chloride is the main component of brine used in tofu, and its taste is bitter. Therefore, seawater with a large proportion of salt tastes salty and bitter.
If all the salt in the seawater is extracted and laid flat on the land, the height of the land can be increased 153 meters; If all the water in the world's oceans evaporates, a 60-meter-thick salt layer will accumulate on the seabed.
Where did so much salt come from in the sea? Scientists compared seawater with river water, studied the soil and gravel after rain, and learned that the salt in seawater was brought by rivers on land through running water. When the rain falls to the ground, it gathers in a lower place, forms a small river, flows into the river, and part of the water seeps into the ground through various strata, then comes out in other areas and finally flows into the sea. In the process of flowing, water passes through various soils and rock formations, and decomposes to produce various salt substances, which are brought into the sea with the current. After the continuous evaporation of seawater, the concentration of salt is getting higher and higher, and the formation of the ocean has gone through hundreds of thousands of years, so it is not surprising that the seawater contains so much salt.