There is much to learn about
salt. Salt, sodium chloride, touches our lives more than any other chemical
compound. The chemical properties and physical properties of sodium chloride
are a treasure to mankind. Salt or salt-derived products are ubiquitous in our
material world and the very cells of our bodies swim in a saline solution. We
take for granted the salt crystals that make our foods safe and palatable and
we give thanks for salt’s lifesaving properties when applied to slick winter
roads. Most are unaware of the 14,000 known uses for salt, how it’s produced
and our success in ensuring the environmental compatibility as it provides the
foundation for the quality of our lives.
Mankind evolved from the sea and
we have a saline “sea” within us as do all fish, reptiles, amphibians, birds,
and mammals. Environmental author Rachel Carson is best known for her book on
birds, but she also wrote The Sea Around Us offering this insight: "When
the animals went ashore to take up life on land, they carried part of the sea
in their bodies, a heritage which they passed on to their children and which
even today links each land animal with its origins in the ancient sea."
Our blood has the same chemical balance of sodium, potassium and calcium found
in the oceans.
salt occurs naturally all over
the world as the mineral halite, as well as in seawater and salt lakes. Some
salt is one the surface, the dried-up residue of ancient seas like the famed
Bonneville Salt Flats in Utah. Surface salt depositions and man-made saltworks
can be seen from space. In ocean coastal areas, saltwater can
"intrude" on underground freshwater supplies, complicating the lives
of those who provide our drinking water supplies. Scientists have also found
salt in meteors and on Mars where its presence signals the possibility of
extra-terrestrial life.
Chemical properties
Tight ionic bonding unites the
elements sodium and chloride to make the chemical compound sodium chloride. Man
has discovered a vast variety of ways to harness the chemical properties of
salt to improve our lives. Chemically, there are many “ salt;” the resulting
compound created by reacting an acid and a base; positively charged metal atoms
(the sodium ion in the case of common salt) replacing the negatively charged
hydrogen atoms of an acid, leaving the chloride ion.
Physical properties
Sodium chloride crystals are
cubic in form and salt crystals are commonly used to exemplify crystalline
structure and many science students are familiar with the process of growing
salt crystals. Its color varies from colorless, when pure, to white, gray or
brownish when in the solid, halite, form. Salt dissolves readily in water. salt
crystals can be grown in various sizes and salt companies prepare particles in
a wide variety of sizes to meet customer needs.
Where is salt found in nature ?
There is enough salt in the oceans
of the world that we could use salt to sculpt a full-scale topographic map of
Europe – five times over. Oceans contain an average of 2.7% salt, by weight
(total solids in seawater average 3.5% and 77% of that is salt). In addition,
evaporation of ancient oceans has left vast deposits of solid (rock) salt over
huge areas of the world. These deposits can be in the form of bedded
sedimentary layers or deep salt domes.
Will we run out of salt?
Never. salt is the most common
and readily available nonmetallic mineral in the world; it is so abundant,
accurate estimates of salt reserves are unavailable. In the United States there
are an estimated 55 trillion metric tons. Since the world uses 240 million tons
of salt a year, U.S. reserves alone could sustain our needs for 100,000 years.
And some of that usage is naturally recycled after use. The enormity of the
Earth’s underground salt deposits, combined with the saline vastness of the
Earth’s oceans makes the supply of salt inexhaustible.
Facts & Statistics
Unlike other strategic minerals,
salt is widely available and produced in countless production units spread
around the globe. The rapid industrialization of East Asia and South Asia have
propelled increases in world salt production with Pakistan just easing past the
United States as the world’s largest salt producing country.