Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. It is the element with the highest atomic number to occur in nature.
|Atomic Mass||224 g.mol-1|
|Discovered by||G.T. Seaborg in 1940|
|Electron configuration||[Rn]5f 67s2|
It was first produced and isolated on December 14, 1940, by a deuteron bombardment of uranium-238 in the 1.5 meters (60 in) cyclotron at the University of California, Berkeley. First, neptunium-238 (half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years).
Properties of Plutonium
- 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.
- At room temperature plutonium is in its α form. This, the most common structural form of the element, is about as hard and brittle as gray cast iron unless it is alloyed with other metals to make it soft and ductile.
- Transuranium elements like Neptunium, Americium, Curium along with Plutonium are a radiological hazard and must be handled carefully with precaution.
- The resistivity of plutonium is very high at room temperature. It is high even at low temperatures.
Uses of Plutonium
- Plutonium isn’t of much use in any application due to its radioactive nature.
- One of the main applications of this element is as a source of energy. It was used in the first atomic bombs.
- The element is used in nuclear weapons as it is a key fissile component and because of its easier availability and ease of fission.