Mendelevium does not occur naturally in the Earth’s crust. It was first synthesized in 1955 by
Glenn T. Seaborg and his team at the University of California using the reactions
253
Es (
4
He, n)
256
Md and
253
Es (
4
He, 2n)
255
Md. Mendelevium is named for the Russian scientist,
Dmitri Mendeleev (Figure 1), who developed the Periodic Table of the chemical
elements
[644,
645]. There are no isotopic applications for isotopes of mendelevium aside
from scientific
research.
Stable
isotope
Relative
atomic mass
Mole
fraction
(none)
Fig. 1: Mendelevium is named after Dmitri Mendeleev to honor his contributions to the
development of the periodic table of the elements. (Photo Source: © 2010 The Regents of the
University of California, Lawrence Berkeley National Laboratory).
Glossary
atomic number (Z) – The number of protons in the nucleus of an atom.
electron – elementary particle of matter with a negative electric charge and a rest mass of about
9.109 × 10
–31
kg.
element (chemical element) – a species of atoms; all atoms with the same number of protons in
the atomic nucleus. A pure chemical substance composed of atoms with the same number of
protons in the atomic nucleus [703].
[return]
neutron – an elementary particle with no net charge and a rest mass of about 1.675 × 10
–27
kg,
slightly more than that of the proton. All atoms contain neutrons in their nucleus except for
protium (
1
H).
proton – an elementary particle having a rest mass of about 1.673 × 10
–27
kg, slightly less than
that of a neutron, and a positive electric charge equal and opposite to that of the electron. The
number of protons in the nucleus of an atom is the atomic number.
References
644.
R. J. Silva. In
The Chemistry of the Actinide and Transactinide Elements (N. M. E.
Lester
R. Morss, Jean Fuger, ed.), pp. 1621. Springer (2006).
645.
L. A. N. Laboratory. Periodic Table of Elements: LANL- Mendelevium. Los Alamos
National Laboratory. 2014 Feb. 25.
http://periodic.lanl.gov/101.shtml
703.
I. U. o. P. a. A. Chemistry.
Compendium of Chemical Terminology, 2nd ed. (the "Gold
Book"). Blackwell Scientific Publications, Oxford (1997).