-
Actinium is a
chemical element; it has
symbol Ac and
atomic number 89. It was
discovered by
Friedrich Oskar Giesel in 1902, who gave it the name emanium;...
- radioactive; its most
stable isotope, francium-223 (originally
called actinium K
after the
natural decay chain in
which it appears), has a half-life of...
-
chemical elements in the 5f series, with
atomic numbers from 89 to 102,
actinium through nobelium.
Number 103, lawrencium, is also
generally included despite...
-
Actinium (89Ac) has no
stable isotopes and no
characteristic terrestrial isotopic composition, thus a
standard atomic weight cannot be given.
There are...
-
Actinium-225 (225Ac, Ac-225) is an
isotope of
actinium. It
undergoes alpha decay to francium-221 with a half-life of 10 days, and is an
intermediate decay...
- Center. The 4n+3
chain of uranium-235 is
commonly called the "
actinium series" or "
actinium cascade".
Beginning with the naturally-occurring
isotope uranium-235...
-
towards high
oxidation states all the way from
actinium to uranium, even
though it is
actually only
actinium and
thorium that have d-block-like configurations...
- Unbiunium, also
known as eka-
actinium or
element 121, is a
hypothetical chemical element; it has
symbol Ubu and
atomic number 121.
Unbiunium and Ubu are...
-
Actinium(III)
oxide is a
chemical compound containing the rare
radioactive element actinium. It has the
formula Ac2O3. It is
similar to its corresponding...
-
chemistry texts often put
scandium (Sc),
yttrium (Y),
lanthanum (La), and
actinium (Ac) in
group 3, so that Ce–Lu and Th–Lr
become the f-block
between groups...
