The most familiar salt is sodium chloride, the principal component of common table salt. Sodium chloride, NaCl, and water, H2O, are formed by neutralization of sodium hydroxide, NaOH, a base, with hydrogen chloride, HCl, an acid: HCl+NaOH→NaCl+H2O. Most salts are ionic compounds (see chemical bond); they are made up of ions rather than molecules. The chemical formula for an ionic salt is an empirical formula; it does not represent a molecule but shows the proportion of atoms of the elements that make up the salt. The formula for sodium chloride, NaCl, indicates that equal numbers of sodium and chlorine atoms combine to form the salt. In the reaction of sodium with chlorine, each sodium atom loses an electron, becoming positively charged, and each chlorine atom gains an electron, becoming negatively charged (see oxidation and reduction); there are equal numbers of positively charged sodium ions and negatively charged chloride ions in sodium chloride. The ions in a solid salt are usually arranged in a definite crystalline structure, each positive ion being associated with a fixed number of negative ions, and vice versa.
A salt that has neither hydrogen (H) nor hydroxyl (OH) in its formula, e.g., sodium chloride (NaCl), is called a normal salt. A salt that has hydrogen in its formula, e.g., sodium bicarbonate (NaHCO3), is called an acid salt. A salt that has hydroxyl in its formula, e.g., basic lead nitrate (Pb[OH]NO3), is called a basic salt. Since a salt may react with a solvent to yield different ions than were present in the salt (see hydrolysis), a solution of a normal salt may be acidic or basic; e.g., trisodium phosphate, Na3PO4, dissolves in and reacts with water to form a basic solution.
In addition to being classified as normal, acid, or basic, salts are categorized as simple salts, double salts, or complex salts. Simple salts, e.g., sodium chloride, contain only one kind of positive ion (other than the hydrogen ion in acid salts). Double salts contain two different positive ions, e.g., the mineral dolomite, or calcium magnesium carbonate, CaMg(CO3)2. Alums are a special kind of double salt. Complex salts, e.g., potassium ferricyanide, K3Fe(CN)6, contain a complex ion that does not dissociate in solution. A hydrate is a salt that includes water in its solid crystalline form; Glauber's salt and Epsom salts are hydrates.
Salts are also prepared by methods other than neutralization. A metal can combine directly with a nonmetal to form a salt; e.g., sodium metal reacts with chlorine gas to form sodium chloride. A metal may react with a dilute acid to form a salt and release hydrogen gas; e.g., zinc reacts with dilute sulfuric acid to form zinc sulfate and hydrogen. A metal oxide may react with an acid to form a salt and water; e.g., calcium oxide reacts with carbonic acid to form calcium carbonate and water. A base can react with a nonmetallic oxide to form a salt and water; e.g., sodium hydroxide reacts with carbon dioxide to form sodium carbonate and water. Two salts may react with one another (in solution) to form two new salts; e.g., barium chloride and sodium sulfate react in solution to form barium sulfate (as an insoluble precipitate) and sodium chloride (which remains in solution). A salt may react with an acid to form a different salt and acid; e.g., sodium chloride and sulfuric acid react when heated to form sodium sulfate and release hydrogen chloride gas (which in solution forms hydrochloric acid). A salt undergoes dissociation when it dissolves in a polar solvent, e.g., water, the extent of dissociation depending both on the salt and the solvent.
See M. Kurlansky, Salt: A World History (2002).
Water that makes up the oceans and seas. Seawater is a complex mixture of 96.5percnt water, 2.5percnt salts, and small amounts of other substances. Much of the world's magnesium is recovered from seawater, as are large quantities of bromine. In certain parts of the world, sodium chloride (table salt) is obtained by evaporating seawater. In addition, desalted seawater can theoretically furnish a limitless supply of drinking water, but the high processing costs are prohibitive. Large desalination plants have been built in dry areas along seacoasts in the Middle East and elsewhere to relieve shortages of fresh water.
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Flat-bottomed depression that is periodically covered by water. Playas occur in interior desert basins and adjacent to coasts in arid and semiarid regions. The water that periodically covers the playa slowly filters into the groundwater system or evaporates into the atmosphere, causing the deposition of salt, sand, and mud along the bottom and around the edges of the depression.
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Largely subsurface geologic structure that consists of a vertical cylinder of salt embedded in horizontal or inclined strata. In the broadest sense, the term includes both the core of salt and the strata that surround and are “domed” by the core. Major accumulations of oil and natural gas are associated with salt domes in the U.S., Mexico, the North Sea, Germany, and Romania; domes along the Gulf Coast contain large quantities of sulfur. Salt domes are also major sources of salt and potash on the Gulf Coast and in Germany, and they have been used for underground storage of liquefied propane gas. Storage “bottles,” made by drilling into the salt and then forming a cavity by subsequent solution, have been considered as sites for disposal of radioactive wastes.
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Chemical compound formed when the hydrogen of an acid is replaced by a metal or its equivalent, such as ammonium (NH4). Typically, an acid and a base react to form a salt and water. Most inorganic salts ionize (see ion) in water solution. Sodium chloride—common table salt—is the most familiar salt; sodium bicarbonate (bicarbonate of soda), silver nitrate, and calcium carbonate are others.
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Naturally occurring sodium chloride (NaCl), common or rock salt. Halite occurs on all continents, in beds that range from a few feet to more than 1,000 ft (300 m) in thickness. Termed evaporite deposits because they formed by the evaporation of saline water in partially enclosed basins, they characteristically are associated with beds of limestone, dolomite, and shale. Halite is found in large deposits in New York and in Russia, France, India, and Canada.
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Negotiations between the U.S. and the Soviet Union aimed at curtailing the manufacture of strategic nuclear missiles. The first round of negotiations began in 1969 and resulted in a treaty regulating antiballistic missiles and freezing the number of intercontinental ballistic missiles and submarine-launched ballistic missiles. It was signed by Leonid Brezhnev and Richard Nixon in 1972. A second round of talks (1972–79), known as SALT II, addressed the asymmetry between the two sides' strategic forces and ended with an agreement to limit strategic launchers (see MIRV). Signed by Brezhnev and Jimmy Carter, it was never formally ratified by the U.S. Senate, though its terms were observed by both sides. Subsequent negotiations took the name Strategic Arms Reduction Talks (START). Seealso intermediate-range nuclear weapons; Nuclear Test-Ban Treaty.
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City (pop., 2000: 181,743), capital of Utah, U.S. Located on the Jordan River, near the southeastern end of Great Salt Lake, it was founded in 1847 by Brigham Young and a group of 148 Mormons as a refuge from religious persecution. It was known as Great Salt Lake City until 1868. It prospered from rail connections to become a hub of western commerce and became the state capital in 1896. The largest city in the state, it lies at an altitude of 4,390 ft (1,338 m). It is a commercial centre for nearby mining operations and has diversified manufacturing industries. It is the headquarters of the Mormon Church of Jesus Christ of Latter-day Saints, which influences the social, economic, political, and cultural life of the state and region. It is the site of the Mormon Temple and Tabernacle. It was the host city of the 2002 Winter Olympic Games.
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Lake, northern Utah, U.S. It is the largest inland body of salt water in the Western Hemisphere and one of the most saline in the world. It fluctuates greatly in size, depending on rates of evaporation and the flow of the rivers into it. Its surface area has varied from about 2,400 sq mi (6,200 sq km) at its highest levels in 1873 and the mid 1980s to about 950 sq mi (2,460 sq km) at its low level in 1963. At times of median water level, it is generally less than 15 ft (4.5 m) deep. Surrounded by stretches of sand, salt land, and marsh, the lake remains isolated, though in recent years it has become important as a source of minerals, as a beach and water-sports attraction, and as a wildlife preserve.
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Salt-n-Pepa is a Grammy-Award Winning American hip hop group from Queens, New York that came into the music scene in 1985 and went on to sell over 13 million albums and singles according to RIAA.com. They are the top selling female rap act, consisting of the lineup of: Cheryl James, now known as Cheryl Wray, and Sandra Denton ("Salt" and "Pepa", respectively), and the group's DJ, Deidra "Dee Dee" Roper (Spinderella).
Hot, Cool & Vicious received some airplay on R&B stations around the country thanks to the songs "My Mic Sound Nice" and "Tramp". But when San Francisco DJ and producer Cameron Paul created a remix of "Push It", the b-side to "Tramp", it gave the group their first major hit single. "Push It" was added to subsequent pressings of Hot, Cool & Vicious and was released as a single, quickly becoming a platinum Top 20 pop hit, receiving a Grammy nomination, and thrusting the album to Platinum album status in the US with 1 million sold, making James, Denton, and Roper the first female rap act to go gold or platinum. The album would eventually sell 1.2 million total worldwide.
Salt-n-Pepa's next album release, 1988s A Salt With a Deadly Pepa, contained the R&B hit and moderate pop hit "Shake Your Thang", featuring the go-go band E.U.. Minor hits were also seen in "Everybody Get Up" and "Twist And Shout", with the latter becoming a #4 pop hit in the UK. The album would sell about 800,000 worldwide with roughly 600,000 of those in the US, attaining gold status.
Their third album, Blacks' Magic, was released in March 1990, and was a personal album for the women on many fronts. Azor —- often late or a no show to their sessions as he was producing other acts -— agreed to let the women work with different producers to finish the album. James and Roper took on producing assignments themselves and the trio also hired different producers for additional songs, such as Invincible's producer Dana Mozie. This would also be the first album to feature Roper on vocals as well as DJ'ing. The result would be six singles and three hits released by Next Plateau Records: "Expression", #1 on the R&B Chart for over 10 weeks and produced by Salt; "Independent"; "I Don't Know" (featuring Kid N Play); "Do You Want Me", (#21 pop); Let's Talk About Sex (Top 20 pop); and "You Showed Me". Pepa would also become the first group member to become pregnant, showcasing her bulging belly in music videos such as "Expression" and "Independent" no matter how much the camera tried to hide it. The album would sell 1.3 million worldwide with a million of those sold in the US. A greatest hits album would later be released called "A Blitz of Salt-N-Pepa Hits", featuring remixed versions of songs from the group's first three albums.
Salt-n-Pepa's fourth studio album Very Necessary, released in September 1993 on London Records (see 1993 in music) was their most successful album to date. Breaking further away from Azor, whom the group accused of not paying them fair royalties, the album featured production by Salt, Pepa, and Spinderella. Buoyed by the singles "Shoop" (co-produced by Pepa and their first US Top Five), "Whatta Man" (featuring En Vogue and also a Top Five hit) and "None of Your Business", the album eventually sold six million worldwide with four million of those in the US (4x platinum) at its time of release, making them the first female rap act to have a multi-platinum album. The group toured and Salt went on to co-star in the motion picture Who's the Man?. Pepa co-starred in the movie Joe's Apartment and began dating Treach of the rap group Naughty By Nature. The trio also won the Grammy Award for Best Rap Performance in 1995 for the single "None Of Your Business", making them the first female rap Grammy winners. In 1995 they also performed at Wrestlemania XI.
Having now broken completely away from Azor, Salt-N-Pepa signed with Red Ant Entertainment and undertook production duties once again. Their fifth album, "Brand New" (1997) released on Red Ant, hit stores a few months later and received good reviews upon release. Red Ant, however, filed for bankruptcy soon afterwards, halting promotion on all its releases, including Salt-n-Pepa's album. The group toured in support of the album, but without any promotion or marketing from the bankrupt label, they only scored minor hits such as "R U Ready" and "Gitty Up". The album sold 700,000 worldwide with 500,000 of those in the US.
In March 1999, Salt-n-Pepa embarked on their final live tour and Pepa married Treach of Naughty By Nature on July 27 1999. Salt-N-Pepa's greatest-hits album, entitled Salt-N-Pepa: The Best Of was released on January 25 2000. Pepa and Treach divorced on July 31 2001 and the group officially disbanded in 2002. Upon disbanding, Salt claimed she had enough of the music industry and would no longer be involved in it. However, all that changed when Salt announced that she would be releasing her first solo CD "Salt of the Earth" which later changed to "Salt Unrapped" but she subsequently did not release the product. Salt has been featured on the remix version of the Salt City Six's "Shine", on the album Holy South: World Wide, a compilation of Chrisitian rap and Christian R&P (Rhythm & Praise) songs. The album was executive produced by ex-Three 6 Mafia member turned Christian rapper, Mr. Del. Salt also revealed in later interviews that she had suffered from bulimia many years ago.
Both Salt and Pepa appeared on VH1's Hip Hop Honors in November 2004. Although Salt-N-Pepa were honorees, they did not perform. Spinderella did not attend. All three women reunited the following year for the next Hip Hop Honors program, performing Whatta Man with En Vogue. It was Salt-N-Pepa's first performance in six years. Salt-N-Pepa reformed in 2007.
Spinderella was a radio personality on KKBT 100.3 in Los Angeles. As of mid-2006, she is still on the radio, hosting (with DJ Mo'Dav.) The Backspin, a nationally-syndicated weekly radio show featuring old school hip hop. Pepa appeared on the fifth season of VH-1's The Surreal Life in 2005. All three members now have children.
On October 14, 2007, The Salt-n-Pepa Show, a reality television show that chronicles events in the lives of the duo as they try to work out the past issues and return to the recording studio is currently airing season 2 on VH1.
On February 18, 2008, Salt-n-Pepa appeared on "Live With Regis and Kelly;" the duo sang "Whatta Man".
On August 26, 2008, Pepa released her autobiography entitled "Let's Talk About Pep". Co-written by best-selling author Karen Hunter, the book offers a glimpse behind the fame, family, failures, and successes of her celebrity life. It features an introduction by Queen Latifah, and an epilogue by Missy Elliott. To accompany the book, she also launched her own social network for her fans at http://www.LetsTalkAboutPep.com