Naphthalene

consists of two BENZENE rings joined together (with the loss of some carbon and hydrogen--condensed) to give the formula C₁₀H₈. It is a white crystalline solid and is obtained from COAL TAR (in the fraction, or part, boiling between 180°C and 200°C) and from PETROLEUM fractions, by demethylation i.e. the removal of the METHYL group from methylnaphthalene. Naphthalene is more reactive than benzene and it is used mostly in the production of plasticizers and resins. Some derivatives of naphthalene are important in the manufacture of dyestuffs.

Taken from Dictionary of Science

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Naphthalene, also known as naphthalin, bicyclo[4.4.0]deca-1,3,5,7,9-pentene or antimite and not to be confused with naphtha, is a crystalline, aromatic, white, solid hydrocarbon with formula C₁₀H₈ and the structure of two fused benzene rings. It is best known as the traditional, primary ingredient of mothballs. It is volatile, forming an inflammable vapor, and readily sublimes at room temperature, producing a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass.

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Valency

is the bonding potential or combining power of an atom or group, measured by the number of hydrogen ions (H⁺, or equivalent) that the atoms could combine with or replace. In an ionic compound, the charge on each ion represents the valency, e.g., in NaCl, both Na⁺ and Cl^- have a valency of one. In covalent compounds, the valency is represented by the number of bonds formed. In carbon dioxide, CO₂, carbon has a valency of 4 and oxygen 2.

The electronic theory of valency explains bonds through the assumption that specific arrangements of outer electrons in atoms (outer shells of eight electrons) give stability (as with the inert gases, which have such a structure) through the transfer or sharing of electrons. Thus with the combination of sodium with chlorine, sodium has one electron in the outer shell, which it loses to chlorine to form the stable structure of the inert gas neon. Similarly, the gain of one electron by chlorine gives it the stable structure of argon.

Taken from Dictionary of Science

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In chemistry, valence, also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element. Over the last century, the concept of valence evolved into a range of approaches for describing the chemical bond, including Lewis structures (1916), valence bond theory (1927), molecular orbitals (1928), valence shell electron pair repulsion theory (1958) and all the advanced methods of quantum chemistry.

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Salt

a compound formed when an ACID reacts with a BASE or when a metal atom replaces one or more hydrogen atoms of an acid. Salts can be formed by other reactions such as two salts reacting together to form different compounds. Salt is also the name given to common salt, or sodium chloride (NaCl), which is found in sea water. It is a vital component of our diet although too much is considered harmful.

Taken from Dictionary of Science

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Salt is a dietary mineral composed primarily of sodium chloride that is essential for animal life, but can be toxic to many land plants. Salt flavor is one of the basic tastes, making salt the oldest, most ubiquitous food seasoning. Salt is also an important preservative.

Salt for human consumption is produced in different forms: unrefined salt (such as sea salt), refined salt (table salt), and iodized salt. It is a crystalline solid, white, pale pink or light gray in color, normally obtained from sea water or rock deposits. Edible rock salts may be slightly grayish in color because of mineral content.

Chloride and sodium ions, the two major components of salt, are necessary for the survival of all known living creatures, including humans. Salt is involved in regulating the water content (fluid balance) of the body. Overconsumption of salt increases the risk of health problems, including high blood pressure.

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Water

hydrogen oxide (H20), a compound that is found everywhere. It can occur as solid, liquid and gas phases. It forms a very large part of the Earth's surface and is vital to life. It occurs in all living organisms and has a remarkable combination of properties in its solvent capacity, chemical stability, thermal properties and abundance.

Taken from Dictionary of Science

Haber Process

the industrial process for the production of ammonia (NH3) by the direct combination of nitrogen and hydrogen in the presence of an iron CATALYST. The process gives a maximum yield (4o per cent) using relatively low temperatures and high pressures. The Haber process is important in industrial chemistry since it is the most economic way to produce ammonia, from which fertilizers are made.

Taken from Dictionary of Science

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The Haber process, also called the Haber–Bosch process, is the nitrogen fixation reaction of nitrogen gas and hydrogen gas, over an enriched iron catalyst, to produce ammonia. The Haber process is important because ammonia is difficult to produce on an industrial scale, and the fertilizer generated from the ammonia is responsible for sustaining one-third of the Earth's population. Despite the fact that 78.1% of the air we breathe is nitrogen, the gas is relatively unreactive because nitrogen molecules are held together by strong triple bonds. It was not until the early 20th century that this method was developed to harness the atmospheric abundance of nitrogen to create ammonia, which can then be oxidized to make the nitrates and nitrites essential for the production of nitrate fertilizer and munitions.

Taken from Wikipedia