Sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...

(₁₆S) has 23 known

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...

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 consis ...

nuclei, in the so-called alpha process of exploding type II supernovas (see

silicon burning In astrophysics, silicon burning is a very brief sequence of nuclear fusion reactions that occur in massive stars with a minimum of about 8–11 solar masses. Silicon burning is the final stage of fusion for massive stars that have run out of the f ...

). Other than ³⁵S, the radioactive isotopes of sulfur are all comparatively short-lived. ³⁵S is formed from cosmic ray spallation of ⁴⁰ Ar in the

atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...

. It has a

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...

of 87 days. The next longest-lived radioisotope is sulfur-38, with a half-life of 170 minutes. The shortest-lived is ⁴⁹S, with a half-life shorter than 200 nanoseconds. Heavier radioactive isotopes of sulfur decay to

chlorine Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...

. When sulfide

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

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 (H2CO3), 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 g ...

s and sulfides can be used to determine the pH and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

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

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

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

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 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 atomic ...

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

, - , rowspan=3, ²⁷SHas 2 halo protons , rowspan=3 style="text-align:right" , 16 , rowspan=3 style="text-align:right" , 11 , rowspan=3, 27.01828(43)# , rowspan=3, 15.5(15) ms , β⁺ (96.6%) , ²⁷P , rowspan=3, (5/2+) , rowspan=3, , rowspan=3, , - , β⁺, p (2.3%) , ²⁶Si , - , β⁺, 2p (1.1%) , ²⁵Al , - , 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 , - , rowspan=2, ²⁹S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 13 , rowspan=2, 28.99661(5) , rowspan=2, 188(4) ms , β⁺ (53.6%) , ²⁹P , rowspan=2, 5/2+# , rowspan=2, , rowspan=2, , - , β⁺, p (46.4%) , ²⁸Si , - , ³⁰S , style="text-align:right" , 16 , style="text-align:right" , 14 , 29.98490677(22) , 1.1759(17) s , β⁺ , ³⁰P , 0+ , , , - , ³¹S , style="text-align:right" , 16 , style="text-align:right" , 15 , 30.97955701(25) , 2.5534(18) s , β⁺ , ³¹P , 1/2+ , , , - , ³²SHeaviest theoretically stable nuclide with equal numbers of protons and neutrons , style="text-align:right" , 16 , style="text-align:right" , 16 , 31.9720711744(14) , colspan=3 align=center, Stable , 0+ , 0.9499(26) , 0.94454-0.95281 , - , ³³S , style="text-align:right" , 16 , style="text-align:right" , 17 , 32.9714589099(15) , colspan=3 align=center, Stable , 3/2+ , 0.0075(2) , 0.00730-0.00793 , - , ³⁴S , style="text-align:right" , 16 , style="text-align:right" , 18 , 33.96786701(5) , colspan=3 align=center, Stable , 0+ , 0.0425(24) , 0.03976-0.04734 , - , ³⁵S , style="text-align:right" , 16 , style="text-align:right" , 19 , 34.96903232(4) , 87.37(4) d , β⁻ , ³⁵Cl , 3/2+ , Trace Cosmogenic , , - , ³⁶S , style="text-align:right" , 16 , style="text-align:right" , 20 , 35.96708070(20) , colspan=3 align=center, StableCan undergo bound-state β⁻ decay to 36Ar, lightest nuclide so capable , 0+ , 0.0001(1) , 0.00013−0.00027 , - , ³⁷S , style="text-align:right" , 16 , style="text-align:right" , 21 , 36.97112551(21) , 5.05(2) min , β⁻ , ³⁷Cl , 7/2− , , , - , ³⁸S , style="text-align:right" , 16 , style="text-align:right" , 22 , 37.971163(8) , 170.3(7) min , β⁻ , ³⁸Cl , 0+ , , , - , ³⁹S , style="text-align:right" , 16 , style="text-align:right" , 23 , 38.97513(5) , 11.5(5) s , β⁻ , ³⁹Cl , (7/2)− , , , - , ⁴⁰S , style="text-align:right" , 16 , style="text-align:right" , 24 , 39.975483(4) , 8.8(22) s , β⁻ , ⁴⁰Cl , 0+ , , , - , rowspan=2, ⁴¹S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 25 , rowspan=2, 40.979593(4) , rowspan=2, 1.99(5) s , β⁻ (>99.9%) , ⁴¹Cl , rowspan=2, 7/2−# , rowspan=2, , rowspan=2, , - , β⁻, n (<.1%) , ⁴⁰Cl , - , rowspan=2, ⁴²S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 26 , rowspan=2, 41.981065(3) , rowspan=2, 1.016(15) s , β⁻ (>96%) , ⁴²Cl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁻, n (<4%) , ⁴¹Cl , - , rowspan=2, ⁴³S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 27 , rowspan=2, 42.986908(5) , rowspan=2, 265(13) ms , β⁻ (60%) , ⁴³Cl , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , β⁻, n (40%) , ⁴²Cl , - , style="text-indent:1em" , ^43mS , colspan="3" style="text-indent:2em" , 319(5) keV , 415.0(26) ns , , , (7/2−) , , , - , rowspan=2, ⁴⁴S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 28 , rowspan=2, 43.990119(6) , rowspan=2, 100(1) ms , β⁻ (81.7%) , ⁴⁴Cl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁻, n (18.2%) , ⁴³Cl , - , style="text-indent:1em" , ^44mS , colspan="3" style="text-indent:2em" , 1365.0(8) keV , 2.619(26) µs , , , 0+ , , , - , rowspan=2, ⁴⁵S , rowspan=2 style="text-align:right" , 16 , rowspan=2 style="text-align:right" , 29 , rowspan=2, 44.99572(111) , rowspan=2, 68(2) ms , β⁻, n (54%) , ⁴⁴Cl , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , β⁻ (46%) , ⁴⁵Cl , - , ⁴⁶S , style="text-align:right" , 16 , style="text-align:right" , 30 , 46.00037(54)# , 50(8) ms , β⁻ , ⁴⁶Cl , 0+ , , , - , ⁴⁷S , style="text-align:right" , 16 , style="text-align:right" , 31 , 47.00791(54)# , 20# ms
200 ns, β⁻ , ⁴⁷Cl , 3/2−# , , , - , ⁴⁸S , style="text-align:right" , 16 , style="text-align:right" , 32 , 48.01370(64)# , 10# ms
200 ns, β⁻ , ⁴⁸Cl , 0+ , , , - , ⁴⁹S , style="text-align:right" , 16 , style="text-align:right" , 33 , 49.02264(72)# , , β⁻ , ⁴⁹Cl , 3/2−# , ,

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