Darmstadtium Atomic number 110 No standard weight Commentary

Darmstadt—Sigurd Hofmann, Gottfried Münzenberg, Peter Armbruster, H. Folger, Fritz Peter Heßberger, H. J. Schött, Victor Ninov elements

Darmstadtium

• The team at Darmstadt bombarded
• lead-208 with nickel-62 nuclei
• to produce one atom of darmstadtium-269
• and one free neutron.
• 208 plus 62,
• take away 1,
• leaves 269,
• having 110 protons
• and 159 neutrons.
• The team deduced the existence
• of the transient darmstadtium atom
• by detecting an alpha decay
• resulting in hassium-265.
• 269 take away 4
• (an alpha particle
• has two protons and two neutrons)
• leaves 265,
• having 108 protons
• and 157 neutrons.

Atomic number 110

• It would have been eka-platinum
• following Mendeleev’s naming convention.
• Before it had been synthesized,
• it was supposed to be ununnilium
• according to the 1979 IUPAC recommendation,
• although most people preferred element 110.
• The Russians wanted to name it becquerelium
• after Henri Becquerel.
• The Americans wanted to name it hahnium
• after Otto Hahn.
• The Germans named it darmstadtium
• after the town where they worked.

No standard weight

• The standard atomic weight of a chemical element
• is the weight of its most common stable isotope,
• which doesn’t work well for elements
• with no stable or common isotope.
• The book says
• “extremely radioactive.”
• If someone you knew
• were this unstable,
• I’m sorry;
• I hope you weren’t very close.