SALT

A BASIC RESOURCE OF ROMANIA

• Romania is a country of considerable potential: rich agricultural lands; diverse energy sources (coal, oil, natural gas, salt); a substantial industrial base encompassing almost the full range of manufacturing activities; an educated work force; and opportunities for expanded development in tourism on the Black Sea and in the Carpathian mountains.

BASIC RESOURCES AND PROCESSING

SALT DEPOSITS

• In Romania, salt deposits can be found in localities which are called salt mines, for example Ocna Sibiului, Ocnele Mari, Ocna Mureş, Ocna Dejului, Târgu Ocna, Slanic Prahova.

• Halite is the mineral form of sodium chloride, NaCl, commonly known as rock salt. Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light or dark blue, purple, pink, red, orange, yellow or gray depending on the amount and type of impurities.

SODIUM CHLORIDE

• Sodium chloride is readily soluble in water and insoluble or only slightly soluble in most other liquids. It forms small, transparent, colorless to white cubic crystals. Sodium chloride is odorless but has a characteristic taste. It is an ionic compound, being made up of equal numbers of positively charged sodium and negatively charged chloride ions .

USES

• It is common for homeowners in cold climates to spread 'rock salt' on their walkways and driveways after a snow storm to melt the ice. It is not necessary to use so much salt that the ice is completely melted; rather, a small amount of salt will weaken the ice so that it can be easily removed by other means. Also, many cities will spread a mixture of sand and salt on roads during and after a snowstorm to improve traction.

• Rock salt may also be used to make ice cream. It is not actually used in the ice cream mixture, but it is used to melt the ice surrounding the can holding the ice cream. Melting is an endothermic process, so when the ice melts it absorbs heat from its surroundings to store as latent heat, thus cooling the ice bath and quickening the freezing process.

Synthetic uses

• Uses of chlorine include PVC, pesticides and epoxy resins. Industrially, elemental chlorine is usually produced by the electrolysis of sodium chloride dissolved in water. Along with chlorine, this chloralkali process yields hydrogen gas and sodium hydroxide, according to the chemical equation:

• 2 NaCl + 2 H2O → Cl2 + H2 + 2 NaOH• Metallic sodium is commercially produced

through the electrolysis of liquid sodium chloride.

Biological uses

• Many micro-organisms cannot live in an overly salty environment: water is drawn out of their cells by osmosis. For this reason salt is used to preserve some foods, such as smoked bacon or fish. It can also be used to detach leeches that have attached themselves to feed. It is also used to disinfect wounds.