Lawrencium (Lr) Element: Important Properties, Discovery, Uses, Effects

Lawrencium is a synthetic chemical element with an atomic number of 103 and is represented by the symbol ‘Lr’ in the periodic table. It is silvery in appearance and belongs to the f-block of period 7 of the periodic table. Lawrencium was identified as the last synthetic trans-uranium element in the actinide series. Similar to other elements in the actinide class, lawrencium exhibits significant radioactivity.

Lawrencium (Lr) Element

Lawrencium was produced independently by a team of scientists from the Joint Institute for Nuclear Research (JINR) in Dubna and the American Lawrence Berkeley Laboratory. In 1961, a team of physicists working at Berkeley, Almon Larsh, Torbjorn Sikkeland, Albert Ghiorso, and Robert Latimer synthesized an atom of lawrencium by blasting a californium target with boron nuclides.

Discovery of Lawrencium

  • Lawrencium was produced independently by a team of scientists from the Joint Institute for Nuclear Research (JINR) in Dubna and the American Lawrence Berkeley Laboratory.
  • Almon Larsh, Torbjorn Sikkeland, Albert Ghiorso, and Robert Latimer, physicists at Berkeley, synthesized an atom of lawrencium in 1961 by blasting a californium target with boron nuclides.
  • Working at the Lawrence Radiation Laboratory in Berkeley, California, the scientists added three micrograms (0.000003 grams) of californium to the target chamber of a linear accelerator.
  • Later, in 1965, a team of scientists from Dubna successfully confirmed the creation of lawrencium.
  • The International Union of Pure and Applied Chemistry (IUPAC) honored both teams for finding lawrencium in 1992.
  • The name lawrencium was officially announced in 1997 and is named after Ernest Lawrence, who invented the cyclotron, which is used to detect radioactive elements.

Occurrence of Lawrencium

  • Lawrencium is a synthetic element that does not occur naturally.
  • Lawrencium is formed through nuclear bombardment and has only been produced in trace amounts.
  • The irradiation of californium-249 with boron-11 ions can produce lawrencium-256.
  • Irradiating berkelium-249 with oxygen(O)-18 ions can produce lawrencium-260.
  • Lawrencium contains ten isotopes having known half-lives, ranging from mass numbers 253 to 262.
  • The element 103 does not have any naturally occurring isotopes.

Elemental Properties of Lawrencium

Electronic Configuration[Rn] 5f14 6d1 7s2
Atomic Number103
Atomic Weight262 g.mol -1
State at 20°CSolid
Group, Period, and BlockActinide, 7, f-block
Density16 g/cm3 at 20 °C
Ionic radiusunknown
Van der Waals radius
Electron shells2, 8, 18, 32, 32, 9, 2
Electrons103
Protons103
Neutrons159 (Varies with isotopes)

Isotopic Information of Lawrencium

  • Lawrencium contains ten isotopes with known half-lives, ranging in mass from 253 to 262. It contains no naturally occurring isotopes.
  • The most stable isotope is lawrencium-266, which has a half-life of 11 hours.
  • Lawrenium-260 has a half-life of around three minutes and is commonly utilized in laboratory research due to its ease of production.
  • Most lawrencium isotopes decay by emitting alpha particles.
  • The lightest isotopes of lawrencium, lawrencium-251 to lawrencium-254, are produced as alpha decay products of dubnium.

Physical Properties of Lawrencium

  • Because of its unstable nature, lawrencium’s physical characteristics are challenging to analyze quantitatively.
  • Atomic mass of the element 103 is 262 u.
  • The final element in the actinide series is lawrencium. On the periodic table, it lies to the left of rutherfordium and to the right of nobelium.
  • It is silvery in appearance.
  • The density of lawrencium is 16gm/cm3.
  • It is the heaviest element among the actinide series.
  • It has the melting point of 1627 degree Celsius, whereas boiling point is yet to be known.
  • Lawrencium is thought to have several physical similarities with lutetium. Its atomic volume is comparable to that of lutetium.
  • Lawrencium is expected to be solid at typical temperatures and pressures.
  • It is projected to have a hexagonally closed-packed structure, similar to lutetium.
  • Lawrencium’s electronic configuration is anomalous.

Chemical Properties of Lawrencium

  • Lawrencium’s unstable nature makes it difficult to conduct statistically significant analyses of its chemical properties.
  • The element 103 is expected to share the chemical properties similar to that of lutetium.
  • It has a comparable enthalpy of sublimation to lutetium.
  • The most common oxidation state for lawrencium is projected to be +3.
  • Lawrencium metal is anticipated to be readily oxidized by oxygen, steam, and acids.
  • The stability of lawrencium(III) compounds in aqueous solution is comparable to that of lutetium(III).
  • Element 103 is believed to generate chloride, fluoride, hydroxide, and hydride.

Synthesis of Lawrencium

  • All elements with atomic numbers more than 100 can only be created through reactions in a particle accelerator, such as a cyclotron; they are not generated in a nuclear reactor.
  • The alpha decay products of dubnium generate the lightest isotopes of lawrencium, which are lawrencium-251 to lawrencium-254.
  • In the same way as lighter lawrencium isotopes, the heaviest lawrencium isotopes: lawrencium-264 to lawrencium-266 are synthesized.
  • After subjecting actinide atoms ranging from americium to einsteinium to light ions ranging from boron to neon, the middle isotopes of lawrencium, lawrencium-255 to lawrencium-262, are created.

Uses of Lawrencium

  • Lawrencium is not very useful because of its radioactive nature. Lawrencium is solely utilized in scientific investigations.
  • Lawrencium is not used commercially because just a few atoms have been produced.
  • This element has technical applications as well as energy harvesting capabilities.
  • 260-Lr is the widely utilized lawrencium in chemistry lab for research purpose due to its greater production.

Health Effects of Lawrencium

  • Lawrencium doesn’t exist naturally, has not yet been discovered in the earth’s crust, and is so unstable that any amount generated would rapidly dissolve into other elements. As a result, there is no reason to worry about its potential health risks.

Environmental Effects of Lawrencium

  • Lawrencium’s short half-life indicates that its effects on the environment are not worth taking into account.

Video Reference

YouTube video

References

  • https://www.periodic-table.org/lawrencium-periodic-table/
  • https://www.lenntech.com/periodic/elements/lr.htm
  • https://periodic-table.com/lawrencium/
  • https://chemicalengineeringworld.com/lawrencium-element-properties-and-information/
  • https://www.chemicool.com/elements/lawrencium.html
  • https://www.vedantu.com/chemistry/lawrencium

About Author

Photo of author

Jyoti Bashyal

Jyoti Bashyal, a graduate of the Central Department of Chemistry, is an avid explorer of the molecular realm. Fueled by her fascination with chemical reactions and natural compounds, she navigates her field's complexities with precision and passion. Outside the lab, Jyoti is dedicated to making science accessible to all. She aspires to deepen audiences' understanding of the wonders of various scientific subjects and their impact on the world by sharing them with a wide range of readers through her writing.

Leave a Comment