Element Lawrencium
It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements.
Like all elements with atomic number over 100, lawrencium can only be produced in particle accelerators by bombarding lighter elements with charged particles.
Lawrencium is a synthetic chemical element with the symbol Lr (formerly Lw) and atomic number 103.
Lawrencium is the final member of the actinide series and is sometimes considered to be a group 3 element, along with scandium, yttrium, and lutetium, as its filled f-shell is expected to make it resemble the 7th-period transition metals.
In the periodic table, it is located to the right of the actinide nobelium, to the left of the 6d transition metal rutherfordium, and under the lanthanide lutetium with which it shares many physical and chemical properties.
In the periodic table, it is located to the right of the actinide nobelium, to the left of the 6d transition metal rutherfordium, and under the lanthanide lutetium with which it shares many physical and chemical properties.
Names and Identifiers
Chemical Formula: | Lr |
CAS: | 22537-19-5 |
Molecular Weight: | 262.11000g/mol |
EC Number : | n/a |
MDL Number: | n/a |
Color: | unknown (presumably metallic/ silvery white/ gray) |
Other Names: | Laurenzio, Laurêncio |
PubChem CID: | 31192 |
IUPAC Name: | Lawrencium |
Inchl: | InChI=1S/Lr |
InChI Key: | CNQCVBJFEGMYDW-UHFFFAOYSA-N |
Canonical SMILES: | [Lr] |
ICSC Number: | n/a |
Physical & Chemical Properties
Phase: | Solid |
Density: | 15.5 g/cm³ |
Boiling Point: | 1900 K (1627 °C, 2961 °F |
Melting Point: | n/a |
Molecular Formula: | Lr |
Flash Point: | n/a |
Exact Mass: | 262.11000 |
Twelve isotopes of lawrencium are known, with mass numbers 252–262 and 266; all are radioactive
Radiosotope data
Isotope | Mass/Da | Half-life | Mode of decay | Nuclear spin | Nuclear magnetic moment |
---|---|---|---|---|---|
255Lr | 255.0967 | 22 s | α to 251Md; EC to 255No | ||
256Lr | 256.0988 | 28 s | α to 252Md; EC to 256No; SF | ||
257Lr | 257.0996 | 0.65 s | α to 253Md; SF | 7/2 | |
258Lr | 258.1019 | 3.9 s | α to 254Md; EC to 258No; SF | ||
259Lr | 259.1030 | 6.1 s | α to 255Md; EC to 259No; SF | ||
260Lr | 260.105320 (60) | 3 m | α to 256Md; EC to 260No; SF | ||
261Lr | 261.1069 | 40 m | SF | ||
262Lr | 262.1097 | 3.6 h | EC to 262No; SF |