Wednesday 13 March 2013

Mendelevium

Mendelevium


Mendelevium is a synthetic element with the symbol Md (formerly Mv) and the atomic number 101. A metallic radioactive transuranic element in the actinide series, mendelevium is usually synthesized by bombarding einsteinium with alpha particles. It was named after Dmitri Ivanovich Mendeleev, who created the Periodic Table. Mendeleev's periodic system is the fundamental way to classify all the chemical elements. The name "mendelevium" was accepted by the International Union of Pure and Applied Chemistry (IUPAC). On the other hand, the proposed symbol "Mv" submitted by the discoverers was not accepted, and IUPAC changed the symbol to "Md" in 1963.

Discovery of Mendelevium

Mendelevium was the ninth synthetic transuranium element of the actinide series to be discovered.

It was first identified by Albert Ghiorso, Bernard Harvey, Gregory Choppin, Stanley Thompson, and Glenn Seaborg in 1955 at the Lawrence Berkeley National Laboratory, California.

Mendelevium-256 (half-life 78.1 minutes) was produced by bombarding einsteinium-253 with alpha particles in the Berkeley 60-inch cyclotron.

Only 17 atoms of mendelevium-256 were initially produced in an all night experiment predicted to produce just one or two atoms of product every three hours. Each nuclear reaction created mendelevium-256 and a neutron.

Mendelevium was identified by chemical analysis in an ion exchange experiment.

The element is named after the Russian chemist Dmitri Mendeleev who devised the first periodic table in modern form.

SymbolMd
Atomic Number101
Atomic Weight258.1
Oxidation States+3
Electronegativity, Pauling1.3
State at RTSolid, Metal
Melting Point, K
Boiling Point, K



Appearance and Characteristics

Harmful effects:

Mendelevium is harmful due to its radioactivity.

Characteristics:

  • Mendelevium is a synthetic, highly radioactive metal and has only been produced in miniscule amounts.
  • Mendelevium was the first element to be produced one atom at a time.
  • Mendelevium metal has not been prepared. 
Uses of Mendelevium

  • Mendelevium is of scientific research interest only.