Salt
From the Simple English Wikipedia, the free encyclopedia that anyone can change
- Salt may also refer to table salt (sodium chloride) or iodised salt.
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In chemistry, a salt is any neutral chemical compound made of cations (positive ions) bound to anions (negative ions). The main type of salt is sodium chloride.
Solutions of salts in water are called electrolytes. Electrolytes, as well as molten salts, conduct electricity.
Salts can melt ice.
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[change] Table Salt
The word "salt" in English often means 'table salt' or 'edible salt' (salt that can be eaten). This is made up mostly of sodium chloride (NaCl). It is one of the few minerals often eaten by humans, but it has other uses besides flavoring food.
There are different kinds of edible salt: unrefined salt (such as sea salt), refined salt (table salt), and iodised salt. It is a crystalline solid that is white, pale pink or light grey in color. It is normally taken from sea water or rock deposits. Natural sea salt includes traces of other minerals besides sodium chloride. Edible rock salts can be a little greyish in color, because of these other minerals.
Sodium (Na) and chlorine (Cl) are the two elements that make up sodium chloride. Both of these are needed for all living creatures, including humans, but they do not need to be eaten in the form of salt, where they are found together in large amounts. Some peoples, such as the Yanomami tribe in South America, have been found to eat very little salt. Salt is used to control the amount of water in the body. Salt flavor is also one of the basic tastes. Salt cravings may be caused by not having enough minerals such as sodium chloride in the body.
Eating too much salt can make health problems more likely to happen, including high blood pressure. In making food, salt is used as a preservative (to make the food last longer) and as a seasoning (for flavor).
[change] Getting table salt
There are different ways to get table salt:
- From the sea, using salt evaporation ponds or desalinisation plants
- From a mountain, or underground, using salt mines.
- From natural brine.
[change] History
Because salt can make things last longer, using it was one of the important things that let civilization get started in places like Egypt. Salt was probably used there as long ago as 4000 BC. In ancient times, salt was worth much more, because it was hard to get, and could be used not only to give foods flavor, but also to make them last longer. Food could now be kept past its season, and taken on long trips.
People often traded salt for other things. It was of high value in China, Greece, the Middle East, and Africa. In the Mediterranean area, including Ancient Rome, salt was even used for money. The word salary comes from the Latin word for salt, because they paid people in salt. After people learned how to get salt from the ocean, salt became cheaper. The Phoenicians were some of the first who figured out how to do this, by pouring seawater on dry land. Then when it dried, they collected the salt and sell it.
Another use of salt was in warfare, as a way to punish a city by ruining its crops. This is called "salting the Earth". The Assyrians are said to have been one of the first to have done this to their neighbours.
[change] Looks
[change] Colour
Salts exist in all different colours, such as yellow (sodium chromate), orange (potassium dichromate), red (mercury sulfide), mauve (cobalt chloride hexahydrate), blue (copper sulfate pentahydrate, ferric hexacyanoferrate), green (nickel oxide), colorless (magnesium sulfate), white (titanium dioxide), and black (manganese dioxide). Most minerals and inorganic pigments as well as many synthetic organic dyes are salts.
