was difficult to find because only traces exist naturally on Earth.
They named it after the Greek word meaning “artificial”
because it was the first man-made element to be found.
It was found in a molybdenum foil deflector
discarded from Ernest Lawrence’s cyclotron in Berkeley.
Lawrence mailed the radioactive foil
to Emilio Segrè and Carlo Perrier in Palermo
who chemically isolated a couple of isotopes,
particularly isotopes technetium-95m and technetium-97.
Atomic number 43
Emilio and Glenn T. Seaborg later found
the isotope technetium-99m,
widely used today for medical diagnostics.
The “m” after the atomic weight signifies
the isotope is metastable, not decaying promptly,
but in this case with a half-life of six hours.
Unstable stuff
Technetium decays;
it doesn’t matter
what isotope you have,
it’s a sandcastle,
a house of cards
that tumbles, or pops.
Many other scientists thought that they had found element 43; however,
their work was not reproducable, mainly because, at least for most of them,
they had found something else.
Many other scientists thought that they had found element 43; however, their work was not reproducable, mainly because, at least for most of them, they had found something else.
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