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Minerals in Detail
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
SULPHUR / SULFUR
Sulphur - chemical details
| Symbol | S |
| Atomic number | 16 |
| Atomic mass | 32.06 g.mol-1 |
| Electronegativity | 2.5 (according to Pauling) |
| Density | 2.07 g.cm-3 at 20 °C |
| Melting point | 113 °C |
| Boiling point | 445 °C |
| Vanderwaals radius | 0.127 nm |
| Ionic radius | 0.184 (-2) nm |
| 0.029 (+6) |
| Isotopes | 5 |
| Electronic configuration | [Ne] 3s23p4 |
| Energy of first ionisation | 999.3 kJ.mol-1 |
| Energy of second ionisation | 2252 kJ.mol-1 |
| Energy of third ionisation | 3357 kJ.mol-1 |
| Standard potential | - 0.51 V |
| Discovered | - The ancients |
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
Sulphur - Description
Sulphur is a multivalent non-metal, abundant, tasteless and odorless. In its native form sulphur is a yellow crystalline solid. In nature it occurs as the
pure element or as sulphide and sulphate minerals. Although sulphur is infamous for its smell, frequently compare to rotten eggs, that odour is actually
characteristic of hydrogen sulphide (H2S).
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
Sulphur - Industrial applications
The most important application of sulphur is in sulphuric acid (H2SO4). It is also used in batteries, gunpowder, fungicides and matches. For details on
industrial applications and impact on the environment see www.lenntech.com/Periodic-chart-elements/S-en.htm
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
Sulphur - In natural form
Sulphur occurs naturally near volcanoes. Many sulphide minerals are known: pyrite and marcaiste are iron sulphide ; stibnite is antimony sulphide; galena is
lead sulphide; cinnabar is mercury sulphide and sphalerite is zinc sulphide. Other, more important, sulphide ores are chalcopyrite, bornite, penlandite,
millerite and molybdenite. The chief source of sulphur for industry is the hydrogen sulphide of natural gas, of which Canada is the main producer.
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
Sulphur - Impact on health
Sulfur is an essential component of all living cells.
In plants and animals the amino acids cysteine and methionine contain sulfur, as do all polypeptides, proteins, and enzymes which contain these amino acids.
Homocysteine and taurine are other sulfur-containing acids which are similar in structure, but which are not coded for by DNA. Glutathione is an important
sulfur-containing tripeptide which plays a role in cells as a source of chemical reduction potential in the cell. Many important cellular enzymes use
prosthetic groups with sulphur input to handle reactions involving acyl-containing biochemicals: two common examples from basic metabolism are coenzyme A
and alpha-lipoic acid.
Disulfide bonds (S-S bonds) formed between cysteine residues in peptide chains are very important in protein assembly and structure. These strong covalent
bonds between peptide chains give proteins a great deal of extra toughness and resiliency. For example, the high strength of feathers and hair is in part
due to their high content of S-S bonds and their high content of cysteine and sulfur (eggs are high in sulfur because large amounts of the element are
necessary for feather formation). The high disulfide content of hair and feathers contributes to their indigestibility, and also their odor when burned.
In traditional medical skin treatment which predates modern era of scientific medicine, elemental sulfur has been used mainly as part of creams to alleviate
various conditions such as psoriasis, eczema and acne. The mechanism of action is not known, although elemental sulfur does oxidize slowly to sulfurous acid,
which in turn (though the action of sulfite) acts as a mild reducing and antibacterial agent.
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