Neptunium is sandwiched on the periodic table between uranium and plutonium, ... Atomic symbol (on the periodic table of elements): Np; Atomic weight (average mass of the atom): 237; ...

Neptunium has 20 isotopes ranging from 225 Np to 244 Np. All the isotopes are radioactive. Its longest-lived isotope is 237 Np with a half-life of 2.14 million years followed by 236 Np with a ...

Oxidation is the process where atoms lose electrons during a chemical reaction. Among the radioactive elements, neptunium and plutonium are much harder to oxidize than uranium.

To measure neptunium-237’s critical mass, the Los Alamos team cast a softball-size, 6-kg sphere of the metal that could nestle within two hemispheres of uranium.

Neptunium and plutonium are harder to oxidize than uranium, making them more difficult to study. To address this challenge, scientists have designed donor ligands—molecules that contribute ...

The main reason neptunium hasn’t been made into a bomb (other than the fact that now that we know it can be, access to it is regulated) is historical.Real work on a nuclear bomb began in the 1940s.

Neptunium, an actinide metal, sits next to uranium in the periodic table with an atomic number of 93; almost self-evidently, its name derives from the planet beyond Uranus in the solar system, ...