Title: Plutonium - Wikipedia
Headings: Plutonium
Plutonium
Contents
Characteristics
Physical properties
Allotropes
Nuclear fission
Isotopes and nucleosynthesis
Decay heat and fission properties
Decay heat of plutonium isotopes
Compounds and chemistry
Electronic structure
Alloys
Occurrence
History
Discovery
Early research
Production during the Manhattan Project
Trinity and Fat Man atomic bombs
Cold War use and waste
Medical experimentation
Applications
Explosives
Mixed oxide fuel
Power and heat source
Precautions
Toxicity
Marine toxicity
Criticality potential
Flammability
Transportation
Land and sea
Air
Notes
Footnotes
Citations
References
External links

Content: The presence of plutonium-240 limits a plutonium sample's usability for weapons or its quality as reactor fuel, and the percentage of plutonium-240 determines its grade ( weapons-grade, fuel-grade, or reactor-grade). Plutonium-238 has a half-life of 87.7 years and emits alpha particles. It is a heat source in radioisotope thermoelectric generators, which are used to power some spacecraft. Plutonium isotopes are expensive and inconvenient to separate, so particular isotopes are usually manufactured in specialized reactors. Producing plutonium in useful quantities for the first time was a major part of the Manhattan Project during World War II that developed the first atomic bombs. The Fat Man bombs used in the Trinity nuclear test in July 1945, and in the bombing of Nagasaki in August 1945, had plutonium cores. Human radiation experiments studying plutonium were conducted without informed consent, and several criticality accidents, some lethal, occurred after the war. Disposal of plutonium waste from nuclear power plants and dismantled nuclear weapons built during the Cold War is a nuclear-proliferation and environmental concern. Other sources of plutonium in the environment are fallout from numerous above-ground nuclear tests, now banned . Contents
1 Characteristics
1.1 Physical properties
1.2 Allotropes
1.3 Nuclear fission
1.4 Isotopes and nucleosynthesis
1.5 Decay heat and fission properties
1.6 Compounds and chemistry
1.6.1 Electronic structure
1.7 Alloys
1.8 Occurrence
2 History
2.1 Discovery
2.2 Early research
2.3 Production during the Manhattan Project
2.4 Trinity and Fat Man atomic bombs
2.5 Cold War use and waste
2.6 Medical experimentation
3 Applications
3.1 Explosives
3.2 Mixed oxide fuel
3.3 Power and heat source
4 Precautions
4.1 Toxicity
4.2 Marine toxicity
4.3 Criticality potential
4.4 Flammability
5 Transportation
5.1 Land and sea
5.2 Air
6 Notes
6.1 Footnotes
6.2 Citations
7 References
8 External links
Characteristics
Physical properties
Plutonium, like most metals, has a bright silvery appearance at first, much like nickel, but it oxidizes very quickly to a dull gray, although yellow and olive green are also reported.