93

Np

Neptunium
[ 237 ]
 Historical Information

Neptunium was the first synthetic transuranium element of the actinide series. It was discovered by McMillan and Abelson in 1940 at Berkeley, California, USA, who bombarded uranium with neutrons produced from a cyclotron. It was the first synthetic transuranium (elements after uranium) element discovered.

Basic Information Shells
  • Name:Neptunium
  • Symbol: Np
  • Atomic number: 93
  • Atomic weight: [ 237 ]
  • Standard state: solid at 298 K
  • Group in periodic table:
  • Group name:Actinoid
  • Period in periodic table: 7
  • Block in periodic table: f-block
  • Classification: Metallic
 Neptunium
Uses Trivia
  • Np-237 is component in neutron detection instruments

Neptunium is a radioactive rare earth metal and has at least 3 allotropic forms. It is named for the planet Neptune. Np-237 is a by-product from nuclear reactors.