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Information about Lawrencium

103nobelium ← lawrencium → rutherfordium
Lu
↑
Lr
↓
(Upt)
Periodic Table - Extended Periodic Table
General
Name, Symbol, Numberlawrencium, Lr, 103
Chemical seriesactinides
Group, Period, Blockn/a, 7, d
Appearanceunknown, probably silvery
white or metallic gray
Standard atomic weight(262) gmol−1
Electron configurationprobably [Rn] 5f14 7s2 7p1
Electrons per shell2, 8, 18, 32, 32, 8, 3
Physical properties
Phasepresumably a solid
Melting point1900 K
(1627 °C, 2961 °F)
Atomic properties
Oxidation states3
Electronegativity1.3 (scale Pauling)
Ionization energies1st: 470 kJ/mol
Miscellaneous
CAS registry number22537-19-5
Selected isotopes
Main article: Isotopes of lawrencium
iso NA half-life DM DE (MeV) DP
262Lrsyn~4 h
References


Lawrencium (IPA: /ləˈrɛnsiəm/) is a radioactive synthetic element in the periodic table that has the symbol Lr (formerly Lw) and atomic number 103. Its most stable isotope is 262Lr, with a half-life of approximately 4 hours. Lawrencium is synthesized from californium and has no known uses.

Notable characteristics

The appearance of this element is unknown, however it is most likely silvery-white or gray and metallic. If sufficient amounts of lawrencium were produced, it would pose a radiation hazard. Very little is known about the chemical properties of this element but some preliminary work on a few atoms has indicated that it behaves similarly to other actinides.

A strict correlation between periodic table blocks and chemical series for neutral atoms would describe lawrencium as a transition metal because it is in the d-block, but it is an actinide according to IUPAC.[1]

History

Lawrencium was discovered by Albert Ghiorso, Torbjørn Sikkeland, Almon Larsh, and Robert M. Latimer on February 14, 1961 at the Lawrence Radiation Laboratory (now called Lawrence Berkeley National Laboratory) on the University of California, Berkeley campus. It was produced by bombarding a three milligram target composed of three isotopes of californium with boron-10 and B-11 ions in the Heavy Ion Linear Accelerator (HILAC).

The transmutation nuclei became electrically charged, recoiled with a helium atmosphere, and were collected on a thin copper conveyor tape. This tape was then moved in order to place the collected atoms in front of a series of solid-state detectors. The Berkeley team reported that the isotope 257103 was detected in this manner and decayed by emitting an 8.6 MeV alpha particle with a half-life of 4.2 seconds.

In 1967, researchers in Dubna, Russia reported that they were not able to confirm an alpha emitter with a half-life of 4.2 seconds as 257103. This assignment has since been changed to 258Lr or 259Lr. Eleven isotopes of element 103 have been synthesized with 262Lr being the longest lived with a half-life of 216 minutes. The isotopes of lawrencium decay via alpha emission, spontaneous fission, and electron capture (in order of most to least common types).

The origin of the name, preferred by the American Chemical Society, is in reference to Ernest O. Lawrence, inventor of the cyclotron. The symbol Lw originally was used but in 1963 it was changed to Lr. In August 1997 the International Union of Pure and Applied Chemistry (IUPAC) ratified the name lawrencium and symbol Lr during a meeting in Geneva. Unniltrium (IPA: /ˌjuːˈnɪltriəm/, symbol Unt) was sometimes used as a temporary, systematic element name until that time. Lawrencium also has been called eka-lutetium.[2]

References

1. ^ IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004) (online draft of an updated version of the "Red Book" IR 3-6)
2. ^ Glenn T. Seaborg (1951-12-12). The transuranium elements: present status (Nobel Lecture).

External links

2, 3
Electronegativity 1.3 (scale Pauling)
Ionization energies 1st: 642 kJ/mol
Miscellaneous
CAS registry number 10028-14-5
Selected isotopes
Main article: Isotopes of nobelium
iso NA half-life DM DE (MeV) DP
253No syn 1.7 m α 8.
..... Click the link for more information.
4
Ionization energies 1st: 580 kJ/mol
Atomic radius (calc.) 150 pm
Covalent radius 74 (calc.) pm
Miscellaneous
CAS registry number 53850-36-5
Selected isotopes
Main article: Isotopes of rutherfordium
iso NA half-life DM DE (MeV) DP

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Lutetium (IPA: /l(j)uːˈtiːʃiəm/) is a chemical element with the symbol Lu and atomic number 71.
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<onlyinclude> This is a list of chemical elements, sorted by name and color coded according to type of element.

Given is each element's element symbol, atomic number, atomic mass or most stable isotope, and group and period numbers on the periodic table.
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<onlyinclude> This is a list of chemical elements by symbol, including the current signification used to identify the chemical elements as recognized by the International Union of Pure and Applied Chemistry, as well as proposed and historical signs.
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A table of chemical elements ordered by atomic number and color coded according to type of element. Given is each element's name, element symbol, group and period, Chemical series, and atomic mass (or most stable isotope).
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A group, also known as a family, is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table.

The modern explanation of the pattern of the periodic table is that the elements in a group have similar
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The actinide (or actinoid) series encompasses the 15 chemical elements that lie between actinium and lawrencium on the periodic table, with atomic numbers 89 - 103[1]. The actinide series derives its name from the first element in the series, actinium.
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A group, also known as a family, is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table.

The modern explanation of the pattern of the periodic table is that the elements in a group have similar
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Periods:]] 1 2 3 4 5 6 7 8
Series Alkalis Alkaline earths Lanthanides Actinides Transition metals Poor metals Metalloids Nonmetals Halogens Noble gases
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A block of the periodic table of elements is a set of adjacent groups. The respective highest-energy electrons in each element in a block belong to the same atomic orbital type.
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group number of lanthanides and actinides. There is no pre-existing physical entity for a "group" of elements. The notion is simply a convenient classification, since some elements have similar periodicities in their properties.
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A period 7 element is one of the chemical elements in the seventh row (or period) of the periodic table of the elements.

This period contains the heaviest element which occurs naturally on earth, uranium.
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D-Block is an American rap group founded in the 1990s by Sheek Louch, Jadakiss and Styles P as The Lox or The L.O.X.. [1] In 2001 the group renamed themselves from "The Lox" to "D-Block".
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Color or colour[1] (see spelling differences) is the visual perceptual property corresponding in humans to the categories called red, yellow, blue, black, etc.
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atomic mass (ma) is the mass of an atom at rest, most often expressed in unified atomic mass units.[1] The atomic mass may be considered to be the total mass of protons, neutrons and electrons in a single atom (when the atom is motionless).
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To help compare different orders of magnitude, the following list describes various mass levels between 10−36 kg and 1053 kg.

Factor (kg) Value Item
10−36 1.
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electron configuration is the arrangement of electrons in an atom, molecule, or other physical structure (e.g., a crystal). Like other elementary particles, the electron is subject to the laws of quantum mechanics, and exhibits both particle-like and wave-like nature.
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Radon (IPA: /ˈreɪdɒn/) is a chemical element that has the symbol Rn and atomic number 86. Radon is a radioactive noble gas that is formed by the decay of radium.
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Electron

Theoretical estimates of the electron density for the first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density
Composition: Elementary particle
Family: Fermion
Group: Lepton
Generation: First
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An electron shell, also known as a main energy level, is a group of atomic orbitals with the same value of the principal quantum number n. Electron shells are made up of one or more electron subshells, or sublevels
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In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i.e. density, crystal structure, index of refraction, and so forth).
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A solid object is in the states of matter characterized by resistance to deformation and changes of volume. At the microscopic scale, a solid has these properties :
  • The atoms or molecules that comprise the solid are packed closely together.

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The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
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The kelvin (symbol: K) is a unit increment of temperature and is one of the seven SI base units. The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero — the coldest possible temperature — is zero kelvins
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Celsius is, or relates to, the Celsius temperature scale (previously known as the centigrade scale). The degree Celsius (symbol: °C) can refer to a specific temperature on the Celsius scale
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Fahrenheit is a temperature scale named after the German-Dutch physicist Daniel Gabriel Fahrenheit (1686–1736), who proposed it in 1724.

In this scale, the melting point of water is 32 degrees Fahrenheit (written “32 °F”), and the boiling point is
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Not to be confused with oxidation state.
The oxidation number of an element in a molecule or complex is the charge that it would have if all the ligands (basically, atoms that donate electrons) were removed along with the electron pairs that were shared
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Electronegativity, symbol χ, is a chemical property which describes the power of an atom (or, more rarely, a functional group) to attract electrons towards itself.[1] First proposed by Linus Pauling in 1932 as a development of valence bond theory,[2]
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