Nagasaki (Japan): 9 August 1945.
Nagasaki (Japan), 9 August 1945
There have only been two. So far. The first was Hiroshima.
The first use of plutonium was as nuclear weapon; United States was the first country to use these weapons against Japan.
It was used first for plutonium production for military purposes.
The first nuclear reaction used to obtain plutonium:238U + n-------239U-------239Np + e--------239Pu + e
The first step is an alpha decay to (guess what!) uranium 235. You can probably take it from there.
Uranium-238 is converted to plutonium-239 in nuclear reactors by absorbing neutrons, which then undergo fission reactions. This conversion process is a key aspect of nuclear reactor operation, particularly in breeder reactors where new fuel is produced while generating energy.
The UK was the third country to obtain nuclear weapons, after the US and the USSR. The UK had its first successful nuclear weapon test in October 1952, a plutonium warhead similar to the one dropped on Nagasaki.
The atomic bomb tested at the Trinity test site in New Mexico during World War II was a plutonium-based implosion-type bomb known as "Gadget." This test marked the first detonation of a nuclear weapon.
Nagasaki (Japan), 9 August 1945
Plutonium was prepared for the first time in December 1940 at Berkeley Laboratory by Glenn Seaborg and collaborators using this nuclear reaction:U-238 + D........Np-238 + 2 n.........Pu-238 + e-