Why is sea water salty

Seawater is a very complex multi-component aqueous solution. All kinds of elements in seawater exist in certain physical and chemical forms. The existence form of copper in seawater is more complex, and most of it exists in the form of organic compounds.

Only a small fraction of the free ions exist in the form of bivalent positive ions and most occur in the form of negative ion complexes. So free copper ions make up only a small fraction of the total dissolved copper. There is an extremely rich content of sodium in seawater, but its chemical behavior is very simple, and it is almost all in the form of Na+ ions.

Dissolved organic matter in seawater is very complex, mainly a substance called "Marine humus", its properties are similar to the humic acid and sensitive acid generated by the decomposition of vegetation in soil. The molecular structure of Marine humus has not been fully determined, but it can form strong compounds with metals.

The water we usually drink is fresh water, only fresh water can sustain human life, the water in the sea as long as the taste is full of salty, why the sea is so salty?

Most of the salt we usually eat comes from the sea, the sea is rich in salt, the most important component of salt - sodium chloride accounted for 9/10 of them, and the remaining 1/10 are magnesium chloride, magnesium carbonate and other elements of salt.

Sodium chloride: The appearance is white crystal, its source is mainly seawater, is the main component of salt.

The taste of sodium chloride we all know is very salty, magnesium chloride we may not be familiar with, but brine we should not be unfamiliar, the brine used for tofu is basically magnesium chloride. Because sea water contains a lot of sodium chloride and magnesium chloride, so the sea water tastes particularly salty, but also with a little bitter.

In fact, although the earliest seawater also contained salt, it was not as impenetrable as it is now. The water in the sea is constantly evaporating, and then rain falls on the ground, and the water on the ground is collected into rivers and lakes and then trickled back to the sea, and at the same time, it brings back various soluble substances from the land, most of which are salts.

Every year, about 3 billion tons of salt flow into the sea along rivers and lakes, and evaporation can't take the salt away. Over time, the salt in the sea became more and more salt, and the sea became the taste of today.

Bottom line: The reason the sea is so salty is because the salt content of the sea is very high. When rivers and lakes enter the sea, they bring salt with them, but when the sea evaporates, the salt does not leave. Over time, more and more salt is trapped in the sea, which is why the water is so salty.