L9 - Phosphorous and Sulphur Flashcards
(31 cards)
What oxidation states can sulphur exist in?
-2 to +6
What are common sulphur minerals?
Sulphides like pyrite (FeS₂)
Sulphates like gypsum (CaSO₄)
Elemental sulphur (S₈)
What are the main sulphur reservoirs?
Atmosphere, hydrosphere, lithosphere, and biosphere.
What are major abiotic sources of sulphur?
Volcanic emissions, sea spray, dust, biomass burning
What is the role of biological assimilation in sulphur cycling?
Plants absorb sulphate and use it to form amino acids.
What happens to sulphur in sediments?
It cycles between forms like elemental sulphur, sulphides, and sulphates through oxidation and biological processes.
How does sulphur move in rivers?
Mainly from weathering of pyrite and gypsum, and enhanced by human activities.
What are key sulphur gases in the atmosphere?
SO₂, H₂S, DMS, OCS, and other biogenic gases.
How is SO₂ converted in the atmosphere?
Oxidised to sulphuric acid (H₂SO₄) through reactions with OH radicals.
What is the main anthropogenic source of sulphur?
Burning fossil fuels (especially coal) and smelting of sulphide ores.
What are the impacts of increased atmospheric sulphur?
Acid rain/fog
More atmospheric particles and thicker clouds
Damage to ecosystems and structures
How can sulphur emissions be mitigated?
Using cleaner fuels
Installing scrubbers in chimneys
Managing landfill emissions
What health impact is associated with PM2.5 particles?
They deposit deep in the lungs and can cause serious respiratory issues.
Does phosphorus have a gaseous state in the atmosphere?
No, phosphorus does not exist significantly in a gaseous form.
How is phosphorus transported through the atmosphere?
Via airborne dust, biological particles, and rain.
In what oxidation state is phosphorus typically found?
+5, as orthophosphate (PO₄³⁻).
What are the natural forms of phosphate?
Inorganic phosphate ion (PO₄³⁻), phosphoric acid (H₃PO₄), and organic phosphate (R-OPO(OH)₂).
What is polyphosphate and how does it form?
Polyphosphate forms by polymerisation of phosphate, biologically or artificially.
Where is most of Earth’s phosphate found?
In apatite minerals within the lithosphere.
Why is phosphorus vital for life?
It’s part of ATP, DNA, RNA, phospholipids, and bones/teeth.
What percentage of eroded phosphorus is dissolved?
Only about 5%.
How does salinity affect phosphorus in estuaries?
Higher salinity promotes the release of phosphorus from particles.
What promotes phosphorus availability in soils?
Biological activity like fungi in the pedosphere.
How does fauna influence phosphorus movement?
Animals redistribute phosphorus through roaming and excretion.
