Phosphorus?

Question

What are some chemical proporties of phosphorus...wat are its uses....where can we find it on our planet and what would it look like...what color is it normally.....is it a solid,liquid,or gas

Answer 1

Phosphorous is a multivalent nonmetal of the nitrogen group. It is found in nature in several allotropic forms, and is an essential element for the life of organisms.

There are several forms of phosphorous, called white, red and black phosphorous, although the their colours are more likely to be slightly different. White phosphorous is the one manufactured industrial; it glows in the dark, is spontaneously flammable when exposed to air and is deadly poison. Red phosphorous can vary in colour from orange to purple, due to slight variations in its chemical structure. The third form, black phosphorous, is made under high pressure, looks like graphite and, like graphite, has the ability to conduct electricity.

Applications

Concentrated phosphoric acids are used in fertilizers for agriculture and farm production. Phosphates are used for special glasses, sodium lamps, in steel production, in military applications (incendiary bombs, smoke screenings etc.), and in other applications as: pyrotechnics, pesticides, toothpaste, detergents.

Phosphorous in the environment

In the natural world phosphorous is never encountered in its pure form, but only as phosphates, which consists of a phosphorous atom bonded to four oxygen atoms. This can exists as the negatively charged phosphate ion (PO43-), which is how it occurs in minerals, or as organophosphates in which there are organic molecules attached to one, two or three of the oxygen atoms.

The amount of phosphorous that is naturally present in food varies considerably but can be as high as 370 mg/100 g in liver, or can be low, as in vegetable oils. Foods rich in phosphorous include tuna, salmon, sardines, liver, turkey, chicken, eggs and cheese (200 g/100 g).

There are many phosphate minerals, the most abundant being forms of apatite. Fluoroapatite provides the most extensively mined deposits. The chief mining areas are Russia, USA, Morocco, Tunisia, Togo and Nauru. World production is 153 million tones per year. There are concerns over how long these phosphorous deposits will last. In case of depletion there could be a serious problem for the worlds food production since phosphorus is such an essential ingredient in fertilizers.

In the oceans, the concentration of phosphates is very low, particularly at the surface. The reason lies partly within the insolubility of aluminum and calcium phosphates, but in any case in the oceans phosphate is quickly used up and falls into the deep as organic debris. There can be more phosphate in rivers and lakes, resulting in excessive algae growth. For further details go to environmental effects of phosphorous.

Answer 2

Phosphorus is a chemical element in the nitrogen group identified by the symbol P on the periodic table of elements.
The nonmetallic element is extremely reactive and also highly toxic, although it is also an important trace mineral in most living organisms.
The discovery of phosphorus is credited to Hennig Brandt, an alchemist who successfully isolated it from urine in the late 1660s. Brandt noted that his discovery possessed the curious property of glowing when it was exposed to air, and he named it phophorus after the Greek phosphoros, meaning "evening star". The atomic number of phophorus is 15, placing it among the lighter chemical elements, and it is rarely if ever found in a pure form.
Like other elements in the nitrogen group, a peculiarity of the structure of phophorus causes it to make very strong bonds with other elements. In addition to making the element highly reactive, this also ensures that it appears in numerous compounds. One of the important groups of phosphorus compounds is the phosphates.
When exposed to air, white phosphorus will begin to burn, and the element also glows in the dark. Expose to heat or light will turn white phosphorus into red phosphorus, a much more stable allotrope which is used to make things like matches. If white phosphorus is heated under pressure, it turns into black phosphorus. All of these forms are pure phosphorus, but they look and behave very differently.
Phosphorus is a key element in all known forms of life.
Today phosphorus production is larger than ever. It is used as a precursor for various chemicals, in particular the herbicide glyphosate sold under the brand name Roundup. Production of white phosphorus takes place at large facilities and it is transported heated in liquid form.
Due to its reactivity with air and many other oxygen-containing substances, phosphorus is not found free in nature but it is widely distributed in many different minerals.

Answer 3

All great answers....all I know is that phosphorus makes a wicked grenades and artillery shells - pieces of the white phosphorus get on your skin and keep burning unless you covered it with water. Viet Cong hated WP "willy pete" rounds....
I also saw two guys (drunk and stoned) toss a WP grenade just outside their hooch thinking it was a smoke grenade...they learned fast what WP can do to you.

Answer 4

Thermite is used for the period of the night to mild up darkish areas and in basic terms from a secure distance from the floor. no longer for the period of the day, fired correct at small infants and wounded human beings. i assume the warfare Crime committee would have yet another information to place a number of those adult men at the back of bars. Thomas

Answer 5

Back to Periodic Table







Phosphorus
Atomic Number: 15 Atomic Radius: 93 pm
Atomic Symbol: P Melting Point: 44.15 (white phosphorus)
Atomic Weight: 30.97376 Boiling Point: 280.5 (white phosphorus)
Electron Configuration: [Ne]3s23p3 Oxidation States: 5, 3, -3
History

(Gr. phosphoros: light bearing; ancient name for the planet Venus when appearing before sunrise) Brand discovered phosphorus in 1669 by preparing it from urine.
Properties

Phosphorus exists in four or more allotropic forms: white (or yellow), red, and black (or violet). Ordinary phosphorus is a waxy white solid; when pure it is colorless and transparent. White phosphorus has two modifications: alpha and beta with a transition temperature at -3.8oC.

It is insoluble in water, but soluble in carbon disulfide. It takes fire spontaneously in air, burning to the pentoxide.
Sources

Never found free in nature, it is widely distributed in combination with minerals. Phosphate rock, which contains the mineral apatite, an impure tri-calcium phosphate, is an important source of the element. Large deposits are found in Russia, in Morocco, and in Florida, Tennessee, Utah, Idaho, and elsewhere.
Handling

Phosphorus is very poisonous, 50 mg constituting an approximate fatal dose. Exposure to white phosphorus should not exceed 0.1 mg/m3 (8-hour time-weighted average per 40-hour work week). White phosphorus should be kept under water (as it is dangerously reactive in air) and should be handled with forceps, as contact with the skin may cause severe burns.

When exposed to sunlight or when heated in its own vapor to 250oC, it is converted to the red variety, which does not phosphoresce in air as does the white variety. This form does not ignite spontaneously and is not as dangerous as white phosphorus. It should, however, be handled with care as it does convert to the white form at some temperatures and it emits highly toxic fumes of the oxides of phosphorus when heated. The red modification is fairly stable, sublimes with a vapor pressure of 1 atm at 17C, and is used in the manufacture of safety matches, pyrotechnics, pesticides, incendiary shells, smoke bombs, tracer bullets, etc.
Production

White phosphorus may be made by several methods. By one process, tri-calcium phosphate, the essential ingredient of phosphate rock, is heated in the presence of carbon and silica in an electric furnace or fuel-fired furnace. Elementary phosphorus is liberated as vapor and may be collected under phosphoric acid, an important compound in making super-phosphate fertilizers.
Uses

In recent years, concentrated phosphoric acids, which may contain as much as 70% to 75% P2O5 content, have become of great importance to agriculture and farm production. World-wide demand for fertilizers has caused record phosphate production. Phosphates are used in the production of special glasses, such as those used for sodium lamps.

Bone-ash --calcium phosphate-- is used to create fine chinaware and to produce mono-calcium phosphate, used in baking powder.

Phosphorus is also important in the production of steels, phosphor bronze, and many other products. Trisodium phosphate is important as a cleaning agent, as a water softener, and for preventing boiler scale and corrosion of pipes and boiler tubes.

Phosphorus is also an essential ingredient of all cell protoplasm, nervous tissue, and bones.

Title Picture: Alchemical symbol for phosphorus.

Sources: CRC Handbook of Chemistry and Physics and the American Chemical Society.

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Answer 6

Phosphorus, (Greek: phôs meaning "light", and phoros meaning "bearer"), is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate rocks.

Due to its high reactivity, phosphorus is never found as a free element in nature. One form of phosphorus (white phosphorus) emits a faint glow upon exposure to oxygen (hence its Greek derivation and the Latin 'light-bearer', meaning the planet Venus as Hesperus or "Morning Star").

Phosphorus is a component of DNA and RNA and an essential element for all living cells. The most important commercial use of phosphorus-based chemicals is the production of fertilisers.

Phosphorus compounds are also widely used in explosives, nerve agents, friction matches, fireworks, pesticides, toothpaste, and detergents.

Elemental phosphorus can exist in several allotropes, most commonly white, red and black.

White phosphorus (P4) exists as individual molecules made up of four atoms in a tetrahedral arrangement, resulting in very high ring strain and instability. It contains 6 single bonds.

White phosphorus is a yellow, waxy transparent solid. For this reason it is also called yellow phosphorus. It glows greenish in the dark (when exposed to oxygen), is highly flammable and pyrophoric (self-igniting) upon contact with air as well as toxic (causing severe liver damage on ingestion). The odour of combustion of this form has a characteristic garlic smell, and samples are commonly coated with white "(di)phosphorus pentoxide", which consists of P4O10 tetrahedra with oxygen inserted between the phosphorus atoms and at their vertices. White phosphorus is insoluble in water but soluble in carbon disulfide.

The white allotrope can be produced using several different methods. In one process, calcium phosphate, which is derived from phosphate rock, is heated in an electric or fuel-fired furnace in the presence of carbon and silica. Elemental phosphorus is then liberated as a vapour and can be collected under phosphoric acid. This process is similar to the first synthesis of phosphorus from calcium phosphate in urine.

Red phosphorus may be formed by heating white phosphorus to 250°C (482°F) or by exposing white phosphorus to sunlight. Phosphorus after this treatment exists as an amorphous network of atoms which reduces strain and gives greater stability; further heating results in the red phosphorus becoming crystalline. Red phosphorus does not catch fire in air at temperatures below 240°C, whereas white phosphorus ignites at about 30°C.

In 1865 Hittorf discovered that when phosphorus was recrystallized from molten lead, a red/purple form is obtained. This purple form is sometimes known as "Hittorf's phosphorus." In addition, a fibrous form exists with similar phosphorus cages. Below is shown a chain of phosphorus atoms which exhibits both the purple and fibrous forms.


One of the forms of red/black phosphorus is a cubic solid.

Black phosphorus has an orthorhombic structure (Cmca) and is the least reactive allotrope, it consists of many six-membered rings which are interlinked. Each atom is bonded to three other atoms.[3][4] A recent synthesis of black phosphorus using metal salts as catalysts has been reported.

The diphosphorus allotrope (P2) can be obtained normally only under extreme conditions (for example, from P4 at 1100 kelvin). Nevertheless, some advancements were obtained in generating the diatomic molecule in homogenous solution, under normal condtitions with the use by some transitional metal complexes (based on for example tungsten and niobium).


Glow

The glow from phosphorus was the attraction of its discovery around 1669, but the mechanism for that glow was not fully described until 1974. It was known from early times that the glow would persist for a time in a stoppered jar but then cease. Robert Boyle in the 1680s ascribed it to "debilitation" of the air; in fact it is oxygen being consumed. By the 18th century it was known that in pure oxygen phosphorus does not glow at all, there is only a range of partial pressure where it does. Heat can be applied to drive the reaction at higher pressures.

In 1974 the glow was explained by R. J. van Zee and A. U. Khan. A reaction with oxygen takes place at the surface of the solid (or liquid) phosphorus, forming the short-lived molecules HPO and P2O2 that both emit visible light. The reaction is slow and only very little of the intermediates is required to produce the luminescence, hence the extended time the glow continues in a stoppered jar.

Although the term phosphorescence is derived from phosphorus, the reaction which gives phosphorus its glow is properly called luminescence (glowing by its own reaction, in this case chemoluminescence), not phosphorescence (re-emitting light that previously fell on it).


Applications

Concentrated phosphoric acids, which can consist of 70% to 75% P2O5 are very important to agriculture and farm production in the form of fertilisers. Global demand for fertilizers led to large increases in phosphate (PO43-) production in the second half of the 20th century. Other uses;

Phosphates are utilized in the making of special glasses that are used for sodium lamps.

Bone-ash, calcium phosphate, is used in the production of fine china.

Sodium tripolyphosphate made from phosphoric acid is used in laundry detergents in several countries, and banned for this use in others.

Phosphoric acid made from elemental phosphorus is used in food applications such as soda beverages. The acid is also a starting point to make food grade phosphates. These include mono-calcium phosphate which is employed in baking powder and sodium tripolyphosphate and other sodium phosphates. Among other uses these are used to improve the characteristics of processed meat and cheese. Others are used in toothpaste. Trisodium phosphate is used in cleaning agents to soften water and for preventing pipe/boiler tube corrosion.

Phosphorus is widely used to make organophosphorus compounds, through the intermediates phosphorus chlorides and the two phosphorus sulfides: phosphorus pentasulfide, and phosphorus sesquisulfide. Organophosphorus compounds have many applications, including in plasticizers, flame retardants, pesticides, extraction agents, and water treatment.
Phosphorus is also an important component in steel production, in the making of phosphor bronze, and in many other related products.
White phosphorus is used in military applications as incendiary bombs, for smoke-screening as smoke pots and smoke bombs, and in tracer ammunition.
Red phosphorus is essential for manufacturing matchbook strikers, flares, safety matches, pharmaceutical grade and street methamphetamine, and is used in cap gun caps.
Phosphorus sesquisulfide is used in heads of strike-anywhere matches.
In trace amounts, phosphorus is used as a dopant for N-type semiconductors.
32P and 33P are used as radioactive tracers in biochemical laboratories (see Isotopes).

Biological role

Phosphorus is a key element in all known forms of life. Inorganic phosphorus in the form of the phosphate PO43- plays a major role in biological molecules such as DNA and RNA where it forms part of the structural framework of these molecules. Living cells also use phosphate to transport cellular energy via adenosine triphosphate (ATP). Nearly every cellular process that uses energy obtains it in the form of ATP. ATP is also important for phosphorylation, a key regulatory event in cells. Phospholipids are the main structural components of all cellular membranes. Calcium phosphate salts assist in stiffening bones.

An average adult human contains a little less than 1 kg of phosphorus, about 85% of which is present in bones and teeth in the form of apatite, and the remainder inside cells in soft tissues. A well-fed adult in the industrialized world consumes and excretes about 1-3 g of phosphorus per day in the form of phosphate. Only about 0.1% of body phosphate circulates in the blood, but this amount reflects the amount of phosphate available to soft tissue cells.

In medicine, low phosphate syndromes are caused by malnutrition, by failure to absorb phosphate, and by metabolic syndromes which draw phosphate from the blood or pass too much of it into the urine. All are characterized by hypophosphatemia (see article for medical details). Symptoms of low phosphate include muscle and neurological dysfunction, and disruption of muscle and blood cells due to lack of ATP.

Phosphorus is an essential macromineral for plants, which is studied extensively in soil conservation in order to understand plant uptake from soil systems. In ecological terms, phosphorus is often a limiting nutrient in many environments; i.e. the availability of phosphorus governs the rate of growth of many organisms. In ecosystems an excess of phosphorus can be problematic, especially in aquatic systems, see eutrophication and algal blooms.


History

Phosphorus (Greek phosphoros was the ancient name for the planet Venus, but in Greek mythology, Hesperus and Eosphorus could be confused with Phosphorus) was discovered by German alchemist Hennig Brand in 1669 through a preparation from urine, which contains considerable quantities of dissolved phosphates from normal metabolism. Working in Hamburg, Brand attempted to distill some salts by evaporating urine, and in the process produced a white material that glowed in the dark and burned brilliantly. Since that time, phosphorescence has been used to describe substances that shine in the dark without burning.

Phosphorus was first made commercially, for the match industry, in the 19th century, by distilling off phosphorus vapor from precipitated phosphates heated in a retort. The precipitated phosphates were made from ground-up bones that had been de-greased and treated with strong acids. This process became obsolete in the late 1890s when the electric arc furnace was adapted to reduce phosphate rock.

Early matches used white phosphorus in their composition, which was dangerous due to its toxicity. Murders, suicides and accidental poisonings resulted from its use. (An apocryphal tale tells of a woman attempting to murder her husband with white phosphorus in his food, which was detected by the stew giving off luminous steam). In addition, exposure to the vapours gave match workers a necrosis of the bones of the jaw, the infamous "phossy jaw." When a safe process for manufacturing red phosphorus was discovered, with its far lower flammability and toxicity, laws were enacted, under a Berne Convention, requiring its adoption as a safer alternative for match manufacture.

The electric furnace method allowed production to increase to the point where phosphorus could be used in weapons of war. In World War I it was used in incendiaries, smoke screens and tracer bullets. A special incendiary bullet was developed to shoot at hydrogen-filled Zeppelins over Britain (hydrogen being highly inflammable if it can be ignited). During World War II, Molotov cocktails of benzene and phosphorus were distributed in Britain to specially selected civilians within the British resistance operation, for defence; and phosphorus incendiary bombs were used in war on a large scale. Burning phosphorus is difficult to extinguish and if it splashes onto human skin it has horrific effects (see precautions below). People covered in it have been known to commit suicide due to the torment.

Today phosphorus production is larger than ever. It is used as a precursor for various chemicals, in particular the herbicide glyphosate sold under the brand name Roundup. Production of white phosphorus takes place at large facilities and it is transported heated in liquid form. Some major accidents have occurred during transportation, train derailments at Brownston, Nebraska and Miamisburg, Ohio led to large fires. The worst accident in recent times was an environmental one in 1968 when phosphorus spilled into the sea from a plant at Placentia Bay, Newfoundland.


Occurrence

Due to its reactivity with air and many other oxygen-containing substances, phosphorus is not found free in nature but it is widely distributed in many different minerals.

Phosphate rock, which is partially made of apatite (an impure tri-calcium phosphate mineral), is an important commercial source of this element. Large deposits of apatite are located in China, Russia, Morocco, Florida, Idaho, Tennessee, Utah, and elsewhere. Albright and Wilson in the United Kingdom and their Niagara Falls plant, for instance, were using phosphate rock in the 1890s and 1900s from Connetable, Tennessee and Florida; by 1950 they were using phosphate rock mainly from Tennessee and North Africa. In the early 1990s Albright and Wilson's purified wet phosphoric acid business was being affected by phosphate rock sales by China and the entry of their long standing Moroccan phosphate suppliers into the purified wet phosphoric acid business.