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Where does salt come from?
Question Date: 2017-03-02
Answer 1:

Salt is sodium chloride NaCl. It forms in saline lakes and in marine environments where there is a LOT of evaporation of water.

So, the analogy is, sprinkle salt into a few table spoons of water; not too much. Make sure the salt crystals all dissolve, then take this salty water and put it on a dish and let the water evaporate. When you come back you will see a crusty white substance... that is halite (NaCl) table salt. Same thing happens in nature in arid environments like in and around the Red Sea and other salt water lagoons in hot dry places.


Answer 2:

There are many types of "salt", and they generally form in the same way. "Salts" are part of a group of minerals called "evaporites", meaning they form from evaporation of water. The most common salt we think of today is known as "table salt" -- the salt you put on your food -- and is usually formed from evaporating seawater (called "sea salt").

This kind of salt is actually a mineral called halite (pronounced, hey-light), and is made of sodium-chloride (NaCl). Because our oceans have lots of dissolved sodium (Na), salt can easily form out of drying seawater. When a pool (or pond) of seawater is stagnant for a while, it allows the sunlight to heat the water. As the water evaporates, it leaves behind the sodium (and other elements, like chlorine). When enough water has evaporated, sodium and chlorine like to bond together to form solid halite (salt).

People have also produced salt from natural spring water in big evaporation pools. These evaporation pools will form salt by allowing water to evaporate, which leaves behind sodium and chlorine (just like evaporating ocean water to form sea salt). Humans have "harvested" salt from the ocean and from spring waters for thousands of years.

There are also deposits of salt within rocks, which can be "mined" and then used. These deposits of salt in rocks, however, were also formed in the same process as modern salt.


Answer 3:

Most salt comes from the evaporation of water saturated with the elements sodium and chlorine. Sometimes it contains salt from ancient seas which dried up, and sometimes the salt forms from the drying of saline lakes like the Aral Sea in Central Asia.

The salt we use doesn't always come from modern seas. For instance, much of Utah and western Colorado contains layers of salt thousands of feet thick buried under layers of sediment. The hidden salt formed from a large shallow sea which concentrated sodium and chlorine from the weathering of mountain ranges which covered Colorado and Utah.

Because salt is so soft, it moves really easily and can pierce through other rock units. Regions in Iran actually contain salt glaciers which can flow over the landscape. This occurs because the region is too arid for rain to dissolve the salt.

Answer 4:

Chemically, salt is the combination of a sodium ion and a chlorine ion. Sodium ion, Na+, has a positive charge on it. The chlorine ion, Cl-, has a negative charge on it. This makes them attracted to each other. Additionally, Cl- has an incomplete octet, and a valence election from Na+ fills that octet, making the pair much more stable and happy.

In a solution of NaCl, the water will eventually evaporate off, forming tiny crystals with a cube like shape, this is called table salt, and it’s what you taste and use on your french fries and other various dishes!

Geographically, salt comes from all around us. Some salt is found underground formed from dried up ancient seas, and some has even arrived from outer space in the form of meteors! Our biggest source of salt is of course, our ocean. Deep shaft mining, solution mining, or solar evaporation are all methods used to extract salt from our external environment. China is the biggest salt producer, followed closely by the US. If we were to extract all of the salt in the sea at this exact moment, it would cover the world’s total land mass to a depth of 35 METERS!


Answer 5:

Salt is a mineral, so we mine it from the earth. There are many kinds of salt, but the kind of salt that we eat on fries is just one variety of salt that we mine from the earth. The scientific name for this kind of salt is halite. When geologists are testing rock for minerals, the best way to check for salt is actually to lick the rock!

When rocks contain a large amount of a valuable mineral, we call this a "deposit". There are some very large salt deposits in the United States, China and Canada. We mine these (get it out from the ground), purify them (remove any unwanted substances so the salt pure) and then package it.


Answer 6:

Salt is a mineral - actually many minerals, but themost common salt on Earth is sodium chloride (NaCl). Different salts are composed of different elements.

Sodium chloride salt dissolves readily in water, which is why the oceans are full of it. Commercial salt is either taken from the sea with the water evaporated off or is mined in salt mines, which are themselves the result of saltwater lakes that dried up leaving the salt behind.



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