| Hazard Information | Back Directory | [Chemical Properties]
discovered in 1955 by Ghiorso and colleagues at Lawrence Berkeley Laboratory; preparation: bombardment of 253Es with He ions [KIR78] | [Definition]
ChEBI: Mendelevium atom is an actinoid atom and a f-block element atom. |
| Questions And Answer | Back Directory | [History]
The element first was made by Ghiorso, Harvey, Choppin, Thompson, and Seaborg in 1955 in Berkeley, California. It was synthesized by bombardment of einsteinium-253 with alpha particles of 41 MeV energy in a 60-inch cyclotron. The element was named Mendelevium in honor of Russian chemist Dimitri Mendeleev. Mendelevium –258 isotope with a half-life of 60 days was discovered in 1967. The element has no commercial use except in research to synthesize isotopes of other transuranium elements.
| [Synthesis]
Mendelevium was synthesized first by bombarding Einstein-253 with helium ions. The nuclear reaction is:
All isotopes of medelevium have been synthesized by other nuclear reactions since its discovery. They are prepared by bombarding uranium, einsteinium, and californium isotopes with heavy ions, such as boron-11, carbon12 and carbon-13.
For example, uranium-238 when bombarded with fluorine-19 produced Md252. Also, certain nuclear reactions carried out by heavy ion projectiles involve ‘stripping’ reactions in which some protons and neutrons may transfer from the projectiles onto the target nucleus, but the latter might not capture the projectile heavy ion. |
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