Sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...

(₁₆S) has 23 known

isotope Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...

s with mass numbers ranging from 27 to 49, four of which are stable: ³²S (95.02%), ³³S (0.75%), ³⁴S (4.21%), and ³⁶S (0.02%). The preponderance of sulfur-32 is explained by its production from carbon-12 plus successive fusion capture of five

helium-4 Helium-4 () is a stable isotope of the element helium. It is by far the more abundant of the two naturally occurring isotopes of helium, making up about 99.99986% of the helium on Earth. Its nucleus is identical to an alpha particle, and consi ...

nuclei, in the so-called

alpha process The alpha process, also known as alpha capture or the alpha ladder, is one of two classes of nuclear fusion reactions by which stars convert helium into heavier elements. The other class is a cycle of reactions called the triple-alpha process, w ...

of exploding type II supernovas (see silicon burning). Other than ³⁵S, the

radioactive isotopes A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ...

of sulfur are all comparatively short-lived. ³⁵S is formed from

cosmic ray spallation Cosmic ray spallation, also known as the x-process, is a set of naturally occurring nuclear reactions causing nucleosynthesis; it refers to the formation of chemical elements from the impact of cosmic rays on an object. Cosmic rays are highly ene ...

of ⁴⁰ Ar in the

atmosphere An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...

. It has a

half-life Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * ''Half Life: ...

of 87 days. The next longest-lived radioisotope is sulfur-38, with a half-life of 170 minutes. Isotopes lighter than ³²S mostly decay to isotopes of phosphorus or

silicon Silicon is a chemical element; it has symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent metalloid (sometimes considered a non-metal) and semiconductor. It is a membe ...

, while ³⁵S and heavier radioisotopes decay to isotopes of chlorine. The beams of several radioactive isotopes (such as those of ⁴⁴S) have been studied theoretically within the framework of the synthesis of superheavy elements, especially those ones in the vicinity of

island of stability In nuclear physics, the island of stability is a predicted set of isotopes of superheavy elements that may have considerably longer half-lives than known isotopes of these elements. It is predicted to appear as an "island" in the chart of nuclid ...

. When sulfide

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...

s are precipitated, isotopic equilibration among solids and liquid may cause small differences in the δ³⁴S values of co-genetic minerals. The differences between minerals can be used to estimate the temperature of equilibration. The δ¹³C and δ³⁴S of coexisting

carbonate A carbonate is a salt of carbonic acid, (), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group ...

s and sulfides can be used to determine the pH and

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

fugacity In thermodynamics, the fugacity of a real gas is an effective partial pressure which replaces the mechanical partial pressure in an accurate computation of chemical equilibrium. It is equal to the pressure of an ideal gas which has the same tempe ...

of the ore-bearing fluid during ore formation. In most

forest A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...

ecosystems, sulfate is derived mostly from the atmosphere; weathering of ore minerals and evaporites also contribute some sulfur. Sulfur with a distinctive isotopic composition has been used to identify pollution sources, and enriched sulfur has been added as a tracer in

hydrologic Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and drainage basin sustainability. A practitioner of hydrology is called a hydro ...

studies. Differences in the

natural abundance In physics, natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the ato ...

s can also be used in systems where there is sufficient variation in the ³⁴S of ecosystem components.

Rocky Mountain The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of Western Canada, to New Mexico in ...

lakes thought to be dominated by atmospheric sources of sulfate have been found to have different δ³⁴S values from oceans believed to be dominated by watershed sources of sulfate.

List of isotopes

, -id=Sulfur-27 , rowspan=3, ²⁷S , rowspan=3 style="text-align:right" , 16 , rowspan=3 style="text-align:right" , 11 , rowspan=3, 27.01878(43)# , rowspan=3, 16.3(2) ms , β⁺, p (61%) , ²⁶Si , rowspan=3, (5/2+) , rowspan=3, , rowspan=3, , - , β⁺ (36%) , ²⁷P , - , β⁺, 2p (3.0%) , ²⁵Al , -id=Sulfur-28 , rowspan=2, ²⁸S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 12 , rowspan=2, 28.00437(17) , rowspan=2, 125(10) ms , β⁺ (79.3%) , ²⁸P , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁺, p (20.7%) , ²⁷Si , -id=Sulfur-29 , rowspan=2, ²⁹S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 13 , rowspan=2, 28.996678(14) , rowspan=2, 188(4) ms , β⁺ (53.6%) , ²⁹P , rowspan=2, 5/2+# , rowspan=2, , rowspan=2, , - , β⁺, p (46.4%) , ²⁸Si , -id=Sulfur-30 , ³⁰S , style="text-align:right" , 16 , style="text-align:right" , 14 , 29.98490677(22) , 1.1798(3) s , β⁺ , ³⁰P , 0+ , , , -id=Sulfur-31 , ³¹S , style="text-align:right" , 16 , style="text-align:right" , 15 , 30.97955700(25) , 2.5534(18) s , β⁺ , ³¹P , 1/2+ , , , -id=Sulfur-32 , ³²SHeaviest theoretically stable nuclide with equal numbers of protons and neutrons , style="text-align:right" , 16 , style="text-align:right" , 16 , 31.9720711735(14) , colspan=3 align=center, Stable , 0+ , 0.9485(255) , , -id=Sulfur-33 , ³³S , style="text-align:right" , 16 , style="text-align:right" , 17 , 32.9714589086(14) , colspan=3 align=center, Stable , 3/2+ , 0.00763(20) , , -id=Sulfur-34 , ³⁴S , style="text-align:right" , 16 , style="text-align:right" , 18 , 33.967867011(47) , colspan=3 align=center, Stable , 0+ , 0.04365(235) , , -id=Sulfur-35 , ³⁵S , style="text-align:right" , 16 , style="text-align:right" , 19 , 34.969032321(43) , 87.37(4) d , β⁻ , ³⁵Cl , 3/2+ , Trace

Cosmogenic Cosmogenic nuclides (or cosmogenic isotopes) are rare nuclides (isotopes) created when a high-energy cosmic ray interacts with the nucleus of an ''in situ'' Solar System atom, causing nucleons (protons and neutrons) to be expelled from the atom ( ...

, , -id=Sulfur-36 , ³⁶S , style="text-align:right" , 16 , style="text-align:right" , 20 , 35.96708069(20) , colspan=3 align=center, Stable , 0+ , 1.58(17)×10⁻⁴ , , -id=Sulfur-37 , ³⁷S , style="text-align:right" , 16 , style="text-align:right" , 21 , 36.97112550(21) , 5.05(2) min , β⁻ , ³⁷Cl , 7/2− , , , -id=Sulfur-38 , ³⁸S , style="text-align:right" , 16 , style="text-align:right" , 22 , 37.9711633(77) , 170.3(7) min , β⁻ , ³⁸Cl , 0+ , , , -id=Sulfur-39 , ³⁹S , style="text-align:right" , 16 , style="text-align:right" , 23 , 38.975134(54) , 11.5(5) s , β⁻ , ³⁹Cl , (7/2)− , , , -id=Sulfur-40 , ⁴⁰S , style="text-align:right" , 16 , style="text-align:right" , 24 , 39.9754826(43) , 8.8(22) s , β⁻ , ⁴⁰Cl , 0+ , , , -id=Sulfur-41 , ⁴¹S , style="text-align:right" , 16 , style="text-align:right" , 25 , 40.9795935(44) , 1.99(5) s , β⁻ , ⁴¹Cl , 7/2−# , , , -id=Sulfur-42 , rowspan=2, ⁴²S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 26 , rowspan=2, 41.9810651(30) , rowspan=2, 1.016(15) s , β⁻ (>96%) , ⁴²Cl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁻, n (<1%) , ⁴¹Cl , -id=Sulfur-43 , rowspan=2, ⁴³S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 27 , rowspan=2, 42.9869076(53) , rowspan=2, 265(13) ms , β⁻ (60%) , ⁴³Cl , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , β⁻, n (40%) , ⁴²Cl , -id=Sulfur-43m , style="text-indent:1em" , ^43mS , colspan="3" style="text-indent:2em" , 320.7(5) keV , 415.0(26) ns , IT , ⁴³S , (7/2−) , , , -id=Sulfur-44 , rowspan=2, ⁴⁴S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 28 , rowspan=2, 43.9901188(56) , rowspan=2, 100(1) ms , β⁻ (82%) , ⁴⁴Cl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁻, n (18%) , ⁴³Cl , -id=Sulfur-44m , style="text-indent:1em" , ^44mS , colspan="3" style="text-indent:2em" , 1365.0(8) keV , 2.619(26) μs , IT , ⁴⁴S , 0+ , , , -id=Sulfur-45 , rowspan=2, ⁴⁵S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 29 , rowspan=2, 44.99641(32)# , rowspan=2, 68(2) ms , β⁻, n (54%) , ⁴⁴Cl , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , β⁻ (46%) , ⁴⁵Cl , -id=Sulfur-46 , ⁴⁶S , style="text-align:right" , 16 , style="text-align:right" , 30 , 46.00069(43)# , 50(8) ms , β⁻ , ⁴⁶Cl , 0+ , , , -id=Sulfur-47 , ⁴⁷S , style="text-align:right" , 16 , style="text-align:right" , 31 , 47.00773(43)# , 24# ms
200 ns, , , 3/2−# , , , -id=Sulfur-48 , ⁴⁸S , style="text-align:right" , 16 , style="text-align:right" , 32 , 48.01330(54)# , 10# ms
200 ns, , , 0+ , , , -id=Sulfur-49 , ⁴⁹S , style="text-align:right" , 16 , style="text-align:right" , 33 , 49.02189(63)# , 4# ms
400 ns, , , 1/2−# , ,

References

External links

Sulfur isotopes data from ''The Berkeley Laboratory Isotopes Project's''
{{Navbox element isotopes Sulfur

List of isotopes

See also

References

External links