Definition

1. Noun:
   • A radioactive transuranic metallic element: Neptunium is a synthetic, heavy metallic element with atomic number 93. It is part of the actinide series and is produced artificially, not found naturally in significant quantities.
   • Found in trace amounts in uranium ores: It occurs in minute quantities as a result of neutron capture in uranium ores.
   • A by-product of the production of plutonium: It is generated during the neutron irradiation of uranium in nuclear reactors.

Usage Examples

• Noun:
  • Neptunium was the first transuranium element to be synthesized.
  • Scientists study the chemistry of neptunium for nuclear fuel cycle applications.
  • Trace amounts of neptunium-237 can be found in uranium ores.

Advanced Usage

• In nuclear chemistry: Neptunium is often discussed in the context of the nuclear fuel cycle, nuclear waste, and the synthesis of heavier elements.
  • The long-lived isotope neptunium-237 is a significant component of spent nuclear fuel.
• In scientific nomenclature: The element is named after the planet Neptune, following the tradition of naming elements after celestial bodies (as uranium is named after Uranus).

Variants and Related Words

• Neptunium series (n): The radioactive decay series that has neptunium-237 as its longest-lived parent isotope.
• Neptunyl (n): A cation containing neptunium in the +6 oxidation state, often studied in solution chemistry (e.g., neptunyl ion, NpO₂²⁺).

Synonyms

• Element 93: Referring to its atomic number.
• Np: Its chemical symbol.

Related Phrases

• Neptunium alloy: A mixture of neptunium with other metals.
  • Research on neptunium alloys is important for understanding its metallurgical properties.
• Neptunium compound: A chemical substance containing neptunium atoms.
  • Neptunium dioxide (NpO₂) is a common compound used in studies.

Noun

1. a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium