All Topics  
Isotopes of uranium

 

 
   Email Print
   Bookmark   Link
 

 

Isotopes of uranium
 
 
  Topics Isotopes of uranium Topic Home

Uranium
Uranium

Uranium is a silvery-gray metallic chemical element in the actinide series of the periodic table that has the chemical symbol U and atomic number 92....
 (U) is a naturally occurring element with no stable isotope
Stable isotope

Stable isotopes are chemical Isotope that are not radioactive . By this definition, there are 256 known stable isotopes of the 80 elements which have one or more stable isotopes....
s. In other words, all uranium is radioactive and hence vanishing by radioactive decay
Radioactive decay

Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting ionizing particles and radiation. This decay, or loss of energy, results in an atom of one type, called the parent nuclide transforming to an atom of a different type, called the daughter nuclide....
, yet it is also found in great quantity in the earth's crust. The natural isotopes are uranium-234
Uranium-234

Uranium-234 is an Isotopes of uranium. In natural uranium and uranium ore, 234U occurs as an indirect decay product of Uranium-238, but it makes up only 0.0055% of the raw uranium because its half-life of just 246,000 years is only about 1/18,000 as long as the half-life of 238U....
, uranium-235
Uranium-235

Uranium-235 is an Isotopes of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding nuclear fission chain reaction, i.e., it is fissile....
, and uranium-238
Uranium-238

Uranium-238 , is the most common Isotopes of uranium of uranium found in nature. When hit by a neutron, it becomes uranium-239 , an unstable isotope which radioactive decay into neptunium-239 , which then itself decays, with a half-life of 2.355 days, into plutonium-239 ....
, with the average atomic mass
Atomic mass

The atomic mass is the mass of an atom, most often expressed in Atomic mass units. The atomic mass may be considered to be the total mass of protons, neutrons and electrons in a single atom ....
 in nature being 238.02891(3) u. In addition, other useful isotopes such as uranium-232
Uranium-232

Uranium 232 is an Isotopes of uranium . It has a half life of 68.9 years and is a side product in the thorium cycle. It has been cited as an obstacle to nuclear proliferation using 233U as the fissile material, because the intense gamma radiation of 232U's decay products makes the 233U contaminated with it mo...
 have been produced in mass quantity in breeder reactor
Breeder reactor

File:Ebr1core.pngA breeder reactor is a nuclear reactor that generates new fissile or Nuclear fuel material at a greater rate than it consumes such material....
s.

Historically, isotopes of uranium were known as

Naturally occurring uranium is composed of three major isotope
Isotope

Isotopes are any of the different types of atoms of the same chemical element, each having a different atomic mass . Isotopes of an element have atomic nucleus with the same number of protons but different numbers of neutron....
s, uranium-238
Uranium-238

Uranium-238 , is the most common Isotopes of uranium of uranium found in nature. When hit by a neutron, it becomes uranium-239 , an unstable isotope which radioactive decay into neptunium-239 , which then itself decays, with a half-life of 2.355 days, into plutonium-239 ....
 (99.28% natural abundance
Natural abundance

In chemistry, natural abundance refers to the abundance 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....
), uranium-235
Uranium-235

Uranium-235 is an Isotopes of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding nuclear fission chain reaction, i.e., it is fissile....
 (0.71%), and uranium-234
Uranium-234

Uranium-234 is an Isotopes of uranium. In natural uranium and uranium ore, 234U occurs as an indirect decay product of Uranium-238, but it makes up only 0.0055% of the raw uranium because its half-life of just 246,000 years is only about 1/18,000 as long as the half-life of 238U....
 (0.0054%).






Discussion
Ask a question about 'Isotopes of uranium'
Start a new discussion about 'Isotopes of uranium'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Uranium
Uranium

Uranium is a silvery-gray metallic chemical element in the actinide series of the periodic table that has the chemical symbol U and atomic number 92....
 (U) is a naturally occurring element with no stable isotope
Stable isotope

Stable isotopes are chemical Isotope that are not radioactive . By this definition, there are 256 known stable isotopes of the 80 elements which have one or more stable isotopes....
s. In other words, all uranium is radioactive and hence vanishing by radioactive decay
Radioactive decay

Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting ionizing particles and radiation. This decay, or loss of energy, results in an atom of one type, called the parent nuclide transforming to an atom of a different type, called the daughter nuclide....
, yet it is also found in great quantity in the earth's crust. The natural isotopes are uranium-234
Uranium-234

Uranium-234 is an Isotopes of uranium. In natural uranium and uranium ore, 234U occurs as an indirect decay product of Uranium-238, but it makes up only 0.0055% of the raw uranium because its half-life of just 246,000 years is only about 1/18,000 as long as the half-life of 238U....
, uranium-235
Uranium-235

Uranium-235 is an Isotopes of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding nuclear fission chain reaction, i.e., it is fissile....
, and uranium-238
Uranium-238

Uranium-238 , is the most common Isotopes of uranium of uranium found in nature. When hit by a neutron, it becomes uranium-239 , an unstable isotope which radioactive decay into neptunium-239 , which then itself decays, with a half-life of 2.355 days, into plutonium-239 ....
, with the average atomic mass
Atomic mass

The atomic mass is the mass of an atom, most often expressed in Atomic mass units. The atomic mass may be considered to be the total mass of protons, neutrons and electrons in a single atom ....
 in nature being 238.02891(3) u. In addition, other useful isotopes such as uranium-232
Uranium-232

Uranium 232 is an Isotopes of uranium . It has a half life of 68.9 years and is a side product in the thorium cycle. It has been cited as an obstacle to nuclear proliferation using 233U as the fissile material, because the intense gamma radiation of 232U's decay products makes the 233U contaminated with it mo...
 have been produced in mass quantity in breeder reactor
Breeder reactor

File:Ebr1core.pngA breeder reactor is a nuclear reactor that generates new fissile or Nuclear fuel material at a greater rate than it consumes such material....
s.

Historically, isotopes of uranium were known as
  • uranium II, 234U
  • actino-uranium, 235U
  • uranium I, 238U


Naturally occurring uranium is composed of three major isotope
Isotope

Isotopes are any of the different types of atoms of the same chemical element, each having a different atomic mass . Isotopes of an element have atomic nucleus with the same number of protons but different numbers of neutron....
s, uranium-238
Uranium-238

Uranium-238 , is the most common Isotopes of uranium of uranium found in nature. When hit by a neutron, it becomes uranium-239 , an unstable isotope which radioactive decay into neptunium-239 , which then itself decays, with a half-life of 2.355 days, into plutonium-239 ....
 (99.28% natural abundance
Natural abundance

In chemistry, natural abundance refers to the abundance 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....
), uranium-235
Uranium-235

Uranium-235 is an Isotopes of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding nuclear fission chain reaction, i.e., it is fissile....
 (0.71%), and uranium-234
Uranium-234

Uranium-234 is an Isotopes of uranium. In natural uranium and uranium ore, 234U occurs as an indirect decay product of Uranium-238, but it makes up only 0.0055% of the raw uranium because its half-life of just 246,000 years is only about 1/18,000 as long as the half-life of 238U....
 (0.0054%). All three isotopes are radioactive
Radioactive decay

Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting ionizing particles and radiation. This decay, or loss of energy, results in an atom of one type, called the parent nuclide transforming to an atom of a different type, called the daughter nuclide....
, creating radioisotope
Radionuclide

A radionuclide is an atom with an unstable Atomic nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created radiation particle within the nucleus, or else to an atomic electron ....
s, with the most abundant and stable being uranium-238 with a half-life
Half-life

The half-life of a quantity whose value decreases with time is the interval required for the quantity to decay to half of its initial value. The concept originated in describing how long it takes atoms to undergo radioactive decay but also applies in a wide variety of other situations....
 of 4.51 years (close to the age of the Earth
Age of the Earth

Modern Geology and geophysicists consider the age of the Earth to be around 1 E17 s This age has been determined by Radiometric dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and Earth's moon Moon rock....
), uranium-235 with a half-life of 7.13 years, and uranium-234 with a half-life of 2.48 years.

Uranium-238 is an a emitter, decaying through the 18-member uranium natural decay series into lead-206. The constant rates of decay in these series makes comparison of the ratios of parent to daughter elements useful in radiometric dating
Radiometric dating

Radiometric dating is a technique used to date materials, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates....
. Uranium-233
Uranium-233

Uranium-233 is a fissile artificial Isotopes of uranium , which has been used in a few nuclear reactors and has been proposed for much wider use as a nuclear fuel....
 is made from thorium-232
Thorium-232

Thorium-232 is the primary abundant nuclide of thorium. It is a slightly unstable radionuclide that is found in the earth's crust. It is a fertile material able to absorb a neutron and undergo Nuclear transmutation into a nuclide that is able to support nuclear fission ....
 by neutron
Neutron

The neutron is a subatomic particle with no net electric charge and a mass slightly larger than that of a proton.Neutrons are usually found in atomic nucleus....
 bombardment.

The isotope uranium-235 is important for both nuclear reactor
Nuclear reactor

A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate, as opposed to a nuclear bomb, in which the chain reaction occurs in a fraction of a second and is uncontrolled causing an explosion....
s and nuclear weapon
Nuclear weapon

A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either nuclear fission or a combination of fission and nuclear fusion....
s because it is the only isotope existing in nature to any appreciable extent that is fissile
Nuclear fission

In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the atomic nucleus of an atom splits into smaller parts, often producing free neutrons and lighter atomic nucleus, which may eventually produce photons ....
, that is, can be broken apart by thermal neutrons. The isotope uranium-238 is also important because it absorbs neutrons to produce a radioactive isotope that subsequently decays to the isotope plutonium-239
Plutonium-239

Plutonium-239 is an isotope of plutonium. Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 has also been used and is currently the secondary isotope....
, which also is fissile.

Table

nuclide
symbol		 Z(p
Proton

The proton is a subatomic particle with an electric charge of +1 elementary charge. It is found in the nucleus of each atom but is also stable by itself and has a second identity as the hydrogen ion, H+....
)		 N(n
Neutron

The neutron is a subatomic particle with no net electric charge and a mass slightly larger than that of a proton.Neutrons are usually found in atomic nucleus....
)		  
isotopic mass (u)
 		 half-life nuclear
spin		 representative
isotopic
composition
(mole fraction)		 range of natural
variation
(mole fraction)
excitation energy
217U 92 125 217.02437(9) 26(14) ms [16(+21-6) ms] 1/2-#  
218U 92 126 218.02354(3) 6(5) ms 0+  
219U 92 127 219.02492(6) 55(25) µs [42(+34-13) µs] 9/2+#  
220U 92 128 220.02472(22)# 60# ns 0+  
221U 92 129 221.02640(11)# 700# ns 9/2+#  
222U 92 130 222.02609(11)# 1.4(7) µs [1.0(+10-4) µs] 0+  
223U 92 131 223.02774(8) 21(8) µs [18(+10-5) µs] 7/2+#  
224U 92 132 224.027605(27) 940(270) µs 0+  
225U 92 133 225.02939# 61(4) ms (5/2+)#  
226U 92 134 226.029339(14) 269(6) ms 0+  
227U 92 135 227.031156(18) 1.1(1) min (3/2+)  
228U 92 136 228.031374(16) 9.1(2) min 0+  
229U 92 137 229.033506(6) 58(3) min (3/2+)  
230U 92 138 230.033940(5) 20.8 d 0+  
231U 92 139 231.036294(3) 4.2(1) d (5/2)(+#)  
232U
Uranium-232

Uranium 232 is an Isotopes of uranium . It has a half life of 68.9 years and is a side product in the thorium cycle. It has been cited as an obstacle to nuclear proliferation using 233U as the fissile material, because the intense gamma radiation of 232U's decay products makes the 233U contaminated with it mo...
 92 140 232.0371562(24) 68.9(4) y 0+  
233U
Uranium-233

Uranium-233 is a fissile artificial Isotopes of uranium , which has been used in a few nuclear reactors and has been proposed for much wider use as a nuclear fuel....
 92 141 233.0396352(29) 1.592(2)×105 y 5/2+  
234U
Uranium-234

Uranium-234 is an Isotopes of uranium. In natural uranium and uranium ore, 234U occurs as an indirect decay product of Uranium-238, but it makes up only 0.0055% of the raw uranium because its half-life of just 246,000 years is only about 1/18,000 as long as the half-life of 238U....
 92 142 234.0409521(20) 2.455(6)×105 y 0+ [0.000054(5)] 0.000050-0.000059
234mU 1421.32(10) keV 33.5(20) µs 6-  
235U
Uranium-235

Uranium-235 is an Isotopes of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding nuclear fission chain reaction, i.e., it is fissile....
 92 143 235.0439299(20) 7.04(1)×108 y 7/2- [0.007204(6)] 0.007198-0.007207
235mU 0.0765(4) keV ~26 min 1/2+  
236U
Uranium-236

Uranium-236 is an Isotopes of uranium that is neither fissile with thermal neutrons, nor very good fertile material, but is generally considered a nuisance and long-lived radioactive waste....
 92 144 236.045568(2) 2.342(3)×107 y 0+  
236m1U 1052.89(19) keV 100(4) ns (4)-  
236m2U 2750(10) keV 120(2) ns (0+)  
237U 92 145 237.0487302(20) 6.75(1) d 1/2+  
238U
Uranium-238

Uranium-238 , is the most common Isotopes of uranium of uranium found in nature. When hit by a neutron, it becomes uranium-239 , an unstable isotope which radioactive decay into neptunium-239 , which then itself decays, with a half-life of 2.355 days, into plutonium-239 ....
 92 146 238.0507882(20) 4.468(3)×109 y 0+ [0.992742(10)] 0.992739-0.992752
238mU 2557.9(5) keV 280(6) ns 0+  
239U
Uranium-239

Uranium-239 is an Isotopes of uranium. It is usually produced by exposing uranium-238 to neutron radiation in a nuclear reactor. Uranium-239 has a half-life of about 23.45 minutes and decays into neptunium-239 through beta decay, with a total decay energy of about 1.29 Mev.....
 92 147 239.0542933(21) 23.45(2) min 5/2+  
239m1U 20(20)# keV >250 ns (5/2+)  
239m2U 133.7990(10) keV 780(40) ns 1/2+  
240U 92 148 240.056592(6) 14.1(1) h 0+  
241U 92 149 241.06033(32)# 5# min 7/2+#  
242U 92 150 242.06293(22)# 16.8(5) min 0+