The Phosphorus Cycle Masta B Yoo, Devin Kim, Drew Li, Justin Yun, Raymond Kim

Basic Chemistry  Essential element of life  Phosphorus is a Group 15 (5A) element  Symbol: P  Atomic number: 15  Atomic mass:  Color: colorless/ red/ silvery white

Basic Chemistry continued  Nonmetal  Density: 1823 kg/m 3  Atomic radius: 100 pm  Solid  Melting Point: K  Boiling Point: 550 K

Basic Chemistry continued  Key ingredient to plants  fertilizers  In nature, Phosphorus exists in form of Phosphate

Basic Chemistry, cont.  Formulas of rocks containing phosphate are fluoroapatite (3Ca 3 (PO 4 ) 2.CaF 2 ), chloroapaptite, (3Ca 3 (PO 4 ) 2.CaCl 2 ), and hydroxyapatite (3Ca 3 (PO 4 ) 2.Ca(OH) 2 )

Description of Phosphorus Most common form of phosphorus is red and white. Most common form of phosphorus is red and white. Both are tetrahedral groups of four atoms. Both are tetrahedral groups of four atoms. White phosphorus burns on contact with air and can change into red phosphorus when exposed to light or heat. White phosphorus burns on contact with air and can change into red phosphorus when exposed to light or heat.

Description of Phosphorus Cont. White phosphorus has two modifications. White phosphorus has two modifications. –Ordinary phosphorus is waxy white solid. –When pure it is colorless and transparent.

Description, Cont. Pure phosphorus is insoluble in water but soluble in carbon disulphide Pure phosphorus is insoluble in water but soluble in carbon disulphide –Catches fire spontaneously in air.

Background Very poisonous Very poisonous Never found in free nature Never found in free nature Essential ingredient of all cell protoplasm, nervous tissue, and bones Essential ingredient of all cell protoplasm, nervous tissue, and bones Most commonly found as phosphates Most commonly found as phosphates Part of DNA materials and energy distribution Part of DNA materials and energy distribution

Uses of Phosphorus Used to make waterproof matches, pyrotechnics, smoke screens, tracer bullets, and incendiary shells. Used to make waterproof matches, pyrotechnics, smoke screens, tracer bullets, and incendiary shells. Used in fertilizer Used in fertilizer Used to produce special glasses, for example sodium lamps Used to produce special glasses, for example sodium lamps

Uses, continued Calcium Phosphate is used to create fine Chinaware Calcium Phosphate is used to create fine Chinaware Monocalcium Phosphate used to make baking powder Monocalcium Phosphate used to make baking powder Used in making steel, and Phosphor Bronze Used in making steel, and Phosphor Bronze Na 3 PO 4 is used as a cleaning agent, water softener, and also prevents corrosion in pipes Na 3 PO 4 is used as a cleaning agent, water softener, and also prevents corrosion in pipes

Hazards and Risks Severely toxic Severely toxic White form is more toxic than red form White form is more toxic than red form Chronic poisoning leads to necrosis of jaw (phossy-jaw) Chronic poisoning leads to necrosis of jaw (phossy-jaw) Phosphate pollution comes from detergents, insecticides, and fertilizers Phosphate pollution comes from detergents, insecticides, and fertilizers Inorganic phosphorus is harmless Inorganic phosphorus is harmless

Background The phosphorus cycle does not have a gas phase, but small amounts of phosphoric acid rise into the atmosphere, contributing to acidic precipitation. The phosphorus cycle does not have a gas phase, but small amounts of phosphoric acid rise into the atmosphere, contributing to acidic precipitation.

Background The water, carbon, and sulfur cycles all include at least one phase in which the element is in its gaseous state. The largest reservoir of phosphorus is in sedimentary rock. The water, carbon, and sulfur cycles all include at least one phase in which the element is in its gaseous state. The largest reservoir of phosphorus is in sedimentary rock.

The Cycle

Description of Cycle Simplest of the cycles Simplest of the cycles Phosphorus has only one form – phosphate Phosphorus has only one form – phosphate –Always part of an organism, dissolved in water, or in the form of rock

Description of Cycle Phosphorus enters environment from rocks or deposits Phosphorus enters environment from rocks or deposits Apatite is the phosphate rock where phosphate is available Apatite is the phosphate rock where phosphate is available Weathering and erosion releases phosphate ions that are soluble in water Weathering and erosion releases phosphate ions that are soluble in water

Description, cont. Phosphate then acts as fertilizers or nutrients for land plants Phosphate then acts as fertilizers or nutrients for land plants It gets incorporated into molecules essential for life like ATP, adenosine triphosphate – this is important in storage and use of energy It gets incorporated into molecules essential for life like ATP, adenosine triphosphate – this is important in storage and use of energy

Description, cont. Phosphate is in backbone of DNA and RNA Phosphate is in backbone of DNA and RNA When animals and plants die, phosphates will return to the soils or oceans again during decay When animals and plants die, phosphates will return to the soils or oceans again during decay

Description, cont. Phosphorus cycles through plants and animals much faster than it does through rocks and sediments.. Phosphorus cycles through plants and animals much faster than it does through rocks and sediments.. A lot of phosphate goes into the water from erosion and leaching A lot of phosphate goes into the water from erosion and leaching Water plants use this phosphate as nutrients Water plants use this phosphate as nutrients

Description, cont. Phosphate is the limiting agent in growth of plants and algae Phosphate is the limiting agent in growth of plants and algae If there is a lack of phosphate, plants grow slowly or are stunted If there is a lack of phosphate, plants grow slowly or are stunted If too much, excess growth may occur If too much, excess growth may occur

Description, cont. Phosphate in water is precipitated from water as ion phosphate (insoluble) Phosphate in water is precipitated from water as ion phosphate (insoluble) Phosphate in shallow sediment may be recycled into water Phosphate in shallow sediment may be recycled into water In deep sediment in water, it is available as part of as part of rock formations for cycle to repeat In deep sediment in water, it is available as part of as part of rock formations for cycle to repeat

Description, cont. After that, phosphorus will end up in sediments or rock formations again, remaining there for millions of years. After that, phosphorus will end up in sediments or rock formations again, remaining there for millions of years. Eventually, phosphorus is released again through weathering and the cycle starts over. Eventually, phosphorus is released again through weathering and the cycle starts over.

Human Influences on Cycle Human influences on phosphate cycle mostly comes from introduction & use of commercial synthetic fertilizers. Human influences on phosphate cycle mostly comes from introduction & use of commercial synthetic fertilizers. Phosphate obtained by mining at certain deposits of calcium phosphate called apatite. Phosphate obtained by mining at certain deposits of calcium phosphate called apatite.

Influences cont. Phosphate rock and sulfuric acid are combined to make a fertilizer called “super phosphate.” Phosphate rock and sulfuric acid are combined to make a fertilizer called “super phosphate.” There are many negative effects of using this fertilizer. There are many negative effects of using this fertilizer.

Influences cont. A lot of the fertilizer is lost through the water run-off because plants aren’t able to use up all of it. A lot of the fertilizer is lost through the water run-off because plants aren’t able to use up all of it. Eventually the wasted phosphate in the water is precipitated as it settles at the bottom of the body of water. Eventually the wasted phosphate in the water is precipitated as it settles at the bottom of the body of water.

Influences cont. In some lakes & ponds the phosphate can be recycled as a problem nutrient. In some lakes & ponds the phosphate can be recycled as a problem nutrient. Other sources of phosphate are in out flows from local sewage treatment plans. Other sources of phosphate are in out flows from local sewage treatment plans.

Interesting Facts Originally, phosphorus was extracted from urine. Originally, phosphorus was extracted from urine. Highly energy intensive. Highly energy intensive. Gr.  phosphoros, meaning “light bearer” Gr.  phosphoros, meaning “light bearer”

Facts, cont. In 1669, German alchemist Henning Brand discovered phosphorus from a preparation from urine. In 1669, German alchemist Henning Brand discovered phosphorus from a preparation from urine. The only correct spelling of the element is phosphorus. There does exist a word phosphorous, but it is the adjectival form for the smaller valency The only correct spelling of the element is phosphorus. There does exist a word phosphorous, but it is the adjectival form for the smaller valency

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