Isotopes of silver
Encyclopedia
Naturally occurring silver
(Ag) is composed of the two stable isotope
s 107Ag and 109Ag with 107Ag being the more abundant (51.839% natural abundance
). Standard atomic mass: 107.8682(2) u.
Twenty-eight radioisotopes have been characterized with the most stable being 105Ag with a half-life
of 41.29 days, 111Ag with a half-life of 7.45 days, and 112Ag with a half-life of 3.13 hours.
All of the remaining radioactive isotopes have half-lives that are less than an hour and the majority of these have half-lives that are less than 3 minutes. This element has numerous meta states with the most stable being 108mAg (t* 418 years), 110mAg (t* 249.79 days) and 106mAg (t* 8.28 days).
Isotopes of silver range in atomic weight
from 92.950 u
(93Ag) to 129.950 u (130Ag). The primary decay mode before the most abundant stable isotope, 107Ag, is electron capture
and the primary mode after is beta decay
. The primary decay product
s before 107Ag are palladium
(element 46) isotopes and the primary products after are cadmium
(element 48) isotopes.
The palladium isotope
107Pd decays by beta emission to 107Ag with a half-life of 6.5 million years. Iron
meteorite
s are the only objects with a high enough palladium/silver ratio to yield measurable variations in 107Ag abundance. Radiogenic 107Ag was first discovered in the Santa Clara
meteorite in 1978.
The discoverers suggest that the coalescence and differentiation of iron-cored small planet
s may have occurred 10 million years after a nucleosynthetic event. 107Pd versus 107Ag correlations observed in bodies, which have clearly been melted since the accretion
of the solar system
, must reflect the presence of live short-lived nuclides in the early solar system.
Standard atomic mass: 107.8682(2) u
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
(Ag) is composed of the two stable isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
s 107Ag and 109Ag with 107Ag being the more abundant (51.839% natural abundance
Natural abundance
In chemistry, natural abundance refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass of these isotopes is the atomic weight listed for the element in the periodic table...
). Standard atomic mass: 107.8682(2) u.
Twenty-eight radioisotopes have been characterized with the most stable being 105Ag with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of 41.29 days, 111Ag with a half-life of 7.45 days, and 112Ag with a half-life of 3.13 hours.
All of the remaining radioactive isotopes have half-lives that are less than an hour and the majority of these have half-lives that are less than 3 minutes. This element has numerous meta states with the most stable being 108mAg (t* 418 years), 110mAg (t* 249.79 days) and 106mAg (t* 8.28 days).
Isotopes of silver range in atomic weight
Atomic weight
Atomic weight is a dimensionless physical quantity, the ratio of the average mass of atoms of an element to 1/12 of the mass of an atom of carbon-12...
from 92.950 u
Atomic mass unit
The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...
(93Ag) to 129.950 u (130Ag). The primary decay mode before the most abundant stable isotope, 107Ag, is electron capture
Electron capture
Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino...
and the primary mode after is beta decay
Beta decay
In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a...
. The primary decay product
Decay product
In nuclear physics, a decay product is the remaining nuclide left over from radioactive decay. Radioactive decay often involves a sequence of steps...
s before 107Ag are palladium
Palladium
Palladium is a chemical element with the chemical symbol Pd and an atomic number of 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired...
(element 46) isotopes and the primary products after are cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
(element 48) isotopes.
The palladium isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
107Pd decays by beta emission to 107Ag with a half-life of 6.5 million years. Iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
s are the only objects with a high enough palladium/silver ratio to yield measurable variations in 107Ag abundance. Radiogenic 107Ag was first discovered in the Santa Clara
Santa Clara, California
Santa Clara , founded in 1777 and incorporated in 1852, is a city in Santa Clara County, in the U.S. state of California. The city is the site of the eighth of 21 California missions, Mission Santa Clara de Asís, and was named after the mission. The Mission and Mission Gardens are located on the...
meteorite in 1978.
The discoverers suggest that the coalescence and differentiation of iron-cored small planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
s may have occurred 10 million years after a nucleosynthetic event. 107Pd versus 107Ag correlations observed in bodies, which have clearly been melted since the accretion
Accretion (astrophysics)
In astrophysics, the term accretion is used for at least two distinct processes.The first and most common is the growth of a massive object by gravitationally attracting more matter, typically gaseous matter in an accretion disc. Accretion discs are common around smaller stars or stellar remnants...
of the solar system
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
, must reflect the presence of live short-lived nuclides in the early solar system.
Standard atomic mass: 107.8682(2) u
Table
| nuclide symbol |
Z(p Proton The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number.... ) |
N(n Neutron The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of... ) |
isotopic mass (u) |
half-life | decay mode(s)Abbreviations: EC: Electron capture Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... IT: Isomeric transition Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer.... |
daughter isotope(s)Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe Age of the universe The age of the universe is the time elapsed since the Big Bang posited by the most widely accepted scientific model of cosmology. The best current estimate of the age of the universe is 13.75 ± 0.13 billion years within the Lambda-CDM concordance model... ) |
nuclear spin |
representative isotopic composition (mole fraction) |
range of natural variation (mole fraction) |
|---|---|---|---|---|---|---|---|---|---|
| excitation energy | |||||||||
| 93Ag | 47 | 46 | 92.94978(64)# | 5# ms [>1.5 µs] |
9/2+# | ||||
| 94Ag | 47 | 47 | 93.94278(54)# | 37(18) ms [26(+26-9) ms] |
β+ Beta decay In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a... |
94Pd | 0+# | ||
| 94m1Ag | 1350(400)# keV | 422(16) ms | β+ (>99.9%) | 94Pd | (7+) | ||||
| β+, p Proton emission Proton emission is a type of radioactive decay in which a proton is ejected from a nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton emission, or can occur from the ground state of very... (<.1%) |
93Rh | ||||||||
| 94m2Ag | 6500(2000)# keV | 300(200) ms | (21+) | ||||||
| 95Ag | 47 | 48 | 94.93548(43)# | 1.74(13) s | β+ (>99.9%) | 95Pd | (9/2+) | ||
| β+, p (<.1%) | 94Rh | ||||||||
| 95m1Ag | 344.2(3) keV | <0.5 s | (1/2-) | ||||||
| 95m2Ag | 2531(1) keV | <16 ms | (23/2+) | ||||||
| 95m3Ag | 4859(1) keV | <40 ms | (37/2+) | ||||||
| 96Ag | 47 | 49 | 95.93068(43)# | 4.45(4) s | β+ (96.3%) | 96Pd | (8+) | ||
| β+, p (3.7%) | 95Rh | ||||||||
| 96m1Ag | 0(50)# keV | 6.9(6) s | (2+) | ||||||
| 96m2Ag | 700(200) ns | ||||||||
| 97Ag | 47 | 50 | 96.92397(35) | 25.3(3) s | β+ | 97Pd | (9/2+) | ||
| 97mAg | 2343(49) keV | 5 ns | (21/2+) | ||||||
| 98Ag | 47 | 51 | 97.92157(7) | 47.5(3) s | β+ (99.99%) | 98Pd | (5+) | ||
| β+, p (.0012%) | 97Rh | ||||||||
| 98mAg | 167.83(15) keV | 220(20) ns | (3+) | ||||||
| 99Ag | 47 | 52 | 98.91760(16) | 124(3) s | β+ | 99Pd | (9/2)+ | ||
| 99mAg | 506.1(4) keV | 10.5(5) s | IT Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer.... |
99Ag | (1/2-) | ||||
| 100Ag | 47 | 53 | 99.91610(8) | 2.01(9) min | β+ | 100Pd | (5)+ | ||
| 100mAg | 15.52(16) keV | 2.24(13) min | IT | 100Ag | (2)+ | ||||
| β+ | 100Pd | ||||||||
| 101Ag | 47 | 54 | 100.91280(11) | 11.1(3) min | β+ | 101Pd | 9/2+ | ||
| 101mAg | 274.1(3) keV | 3.10(10) s | IT | 101Ag | 1/2- | ||||
| 102Ag | 47 | 55 | 101.91169(3) | 12.9(3) min | β+ | 102Pd | 5+ | ||
| 102mAg | 9.3(4) keV | 7.7(5) min | β+ (51%) | 102Pd | 2+ | ||||
| IT (49%) | 102Ag | ||||||||
| 103Ag | 47 | 56 | 102.908973(18) | 65.7(7) min | β+ | 103Pd | 7/2+ | ||
| 103mAg | 134.45(4) keV | 5.7(3) s | IT | 103Ag | 1/2- | ||||
| 104Ag | 47 | 57 | 103.908629(6) | 69.2(10) min | β+ | 104Pd | 5+ | ||
| 104mAg | 6.9(4) keV | 33.5(20) min | β+ (99.93%) | 104Pd | 2+ | ||||
| IT (.07%) | 104Ag | ||||||||
| 105Ag | 47 | 58 | 104.906529(12) | 41.29(7) d | β+ | 105Pd | 1/2- | ||
| 105mAg | 25.465(12) keV | 7.23(16) min | IT (99.66%) | 105Ag | 7/2+ | ||||
| β+ (.34%) | 105Pd | ||||||||
| 106Ag | 47 | 59 | 105.906669(5) | 23.96(4) min | β+ (99.5%) | 106Pd | 1+ | ||
| β- (0.5%) | 106Cd | ||||||||
| 106mAg | 89.66(7) keV | 8.28(2) d | β+ | 106Pd | 6+ | ||||
| IT (4.16×10−6%) | 106Ag | ||||||||
| 107AgUsed to date certain events in the early history of the Solar System | 47 | 60 | 106.905097(5) | Observationally StableTheoretically capable of spontaneous fission Spontaneous fission Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses... |
1/2- | 0.51839(8) | |||
| 107mAg | 93.125(19) keV | 44.3(2) s | IT | 107Ag | 7/2+ | ||||
| 108Ag | 47 | 61 | 107.905956(5) | 2.37(1) min | β- (97.15%) | 108Cd | 1+ | ||
| β+ (2.85%) | 108Pd | ||||||||
| 108mAg | 109.440(7) keV | 418(21) a | β+ (91.3%) | 108Pd | 6+ | ||||
| IT (8.96%) | 108Ag | ||||||||
| 109AgFission product Fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The... |
47 | 62 | 108.904752(3) | Observationally Stable | 1/2- | 0.48161(8) | |||
| 109mAg | 88.0341(11) keV | 39.6(2) s | IT | 109Ag | 7/2+ | ||||
| 110Ag | 47 | 63 | 109.906107(3) | 24.6(2) s | β- (99.7%) | 110Cd | 1+ | ||
| EC Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... (.3%) |
110Pd | ||||||||
| 110m1Ag | 1.113 keV | 660(40) ns | 2- | ||||||
| 110m2Ag | 117.59(5) keV | 249.950(24) d | β- (98.64%) | 110Cd | 6+ | ||||
| IT (1.36%) | 110Ag | ||||||||
| 111Ag | 47 | 64 | 110.905291(3) | 7.45(1) d | β- | 111Cd | 1/2- | ||
| 111mAg | 59.82(4) keV | 64.8(8) s | IT (99.3%) | 111Ag | 7/2+ | ||||
| β- (.7%) | 111Cd | ||||||||
| 112Ag | 47 | 65 | 111.907005(18) | 3.130(9) h | β- | 112Cd | 2(-) | ||
| 113Ag | 47 | 66 | 112.906567(18) | 5.37(5) h | β- | 113mCd | 1/2- | ||
| 113mAg | 43.50(10) keV | 68.7(16) s | IT (64%) | 113Ag | 7/2+ | ||||
| β- (36%) | 113Cd | ||||||||
| 114Ag | 47 | 67 | 113.908804(27) | 4.6(1) s | β- | 114Cd | 1+ | ||
| 114mAg | 199(5) keV | 1.50(5) ms | IT | 114Ag | (<7+) | ||||
| 115Ag | 47 | 68 | 114.90876(4) | 20.0(5) min | β- | 115mCd | 1/2- | ||
| 115mAg | 41.16(10) keV | 18.0(7) s | β- (79%) | 115Cd | 7/2+ | ||||
| IT (21%) | 115Ag | ||||||||
| 116Ag | 47 | 69 | 115.91136(5) | 2.68(10) min | β- | 116Cd | (2)- | ||
| 116mAg | 81.90(20) keV | 8.6(3) s | β- (94%) | 116Cd | (5+) | ||||
| IT (6%) | 116Ag | ||||||||
| 117Ag | 47 | 70 | 116.91168(5) | 73.6(14) s [72.8(+20-7) s] |
β- | 117mCd | 1/2-# | ||
| 117mAg | 28.6(2) keV | 5.34(5) s | β- (94%) | 117mCd | (7/2+) | ||||
| IT (6%) | 117Ag | ||||||||
| 118Ag | 47 | 71 | 117.91458(7) | 3.76(15) s | β- | 118Cd | 1- | ||
| 118m1Ag | 45.79(9) keV | ~0.1 µs | 0(-) to 2(-) | ||||||
| 118m2Ag | 127.49(5) keV | 2.0(2) s | β- (59%) | 118Cd | 4(+) | ||||
| IT (41%) | 118Ag | ||||||||
| 118m3Ag | 279.37(20) keV | ~0.1 µs | (2+,3+) | ||||||
| 119Ag | 47 | 72 | 118.91567(10) | 6.0(5) s | β- | 119mCd | 1/2-# | ||
| 119mAg | 20(20)# keV | 2.1(1) s | β- | 119Cd | 7/2+# | ||||
| 120Ag | 47 | 73 | 119.91879(8) | 1.23(4) s | β- (99.99%) | 120Cd | 3(+#) | ||
| β-, n Neutron emission Neutron emission is a type of radioactive decay of atoms containing excess neutrons, in which a neutron is simply ejected from the nucleus. Two examples of isotopes which emit neutrons are helium-5 and beryllium-13... (.003%) |
119Cd | ||||||||
| 120mAg | 203.0(10) keV | 371(24) ms | β- (63%) | 120Cd | 6(-) | ||||
| IT (37%) | 120Ag | ||||||||
| 121Ag | 47 | 74 | 120.91985(16) | 0.79(2) s | β- (99.92%) | 121Cd | (7/2+)# | ||
| β-, n (.076%) | 120Cd | ||||||||
| 122Ag | 47 | 75 | 121.92353(22)# | 0.529(13) s | β- (>99.9%) | 122Cd | (3+) | ||
| β-, n (<.1%) | 121Cd | ||||||||
| 122mAg | 80(50)# keV | 1.5(5) s | β- (>99.9%) | 122Cd | 8-# | ||||
| β-, n (<.1%) | 121Cd | ||||||||
| 123Ag | 47 | 76 | 122.92490(22)# | 0.300(5) s | β- (99.45%) | 123Cd | (7/2+) | ||
| β-, n (.549%) | 122Cd | ||||||||
| 124Ag | 47 | 77 | 123.92864(21)# | 172(5) ms | β- (99.9%) | 124Cd | 3+# | ||
| β-, n (.1%) | 123Cd | ||||||||
| 124mAg | 0(100)# keV | 200# ms | β- | 124Cd | 8-# | ||||
| IT | 124Ag | ||||||||
| 125Ag | 47 | 78 | 124.93043(32)# | 166(7) ms | β- (>99.9%) | 125Cd | (7/2+)# | ||
| β-, n (<.1%) | 124Cd | ||||||||
| 126Ag | 47 | 79 | 125.93450(32)# | 107(12) ms | β- (>99.9%) | 126Cd | 3+# | ||
| β-, n (<.1%) | 125Cd | ||||||||
| 127Ag | 47 | 80 | 126.93677(32)# | 79(3) ms | β- (>99.9%) | 127Cd | 7/2+# | ||
| β-, n (<.1%) | 126Cd | ||||||||
| 128Ag | 47 | 81 | 127.94117(32)# | 58(5) ms | |||||
| 129Ag | 47 | 82 | 128.94369(43)# | 44(7) ms [46(+5-9) ms] |
7/2+# | ||||
| 129mAg | 0(200)# keV | ~160 ms | 1/2-# | ||||||
| 130Ag | 47 | 83 | 129.95045(36)# | ~50 ms | 0+ | ||||