Difference Between Uranium and Plutonium

Uranium vs Plutonium
 

Uranium and plutonium are radioactive elements in the actinide series.

Uranium

The symbol of uranium is U, and it is the 92^nd element in the periodic table. So it has 92 electrons and 92 protons.  Electron configuration of uranium can be written as [Rn] 5f³ 6d¹ 7s². It has six valence electrons, which are in s, d and f orbitals. Uranium is in the actinide series.  It is a silvery white color solid. Uranium is considered as a metallic chemical element. Uranium is hard, malleable, and ductile. Though it is considered as a metal, it is a poor electric conductor. But it is strongly electropositive. Moreover, uranium is slightly paramagnetic. Uranium has a very high density, which is about 19.1 g·cm⁻³. Uranium, being a metal, reacts with most of the nonmetal elements and their compounds. The reactivity increases with temperature. Strong acids like hydrochloric and nitric acids are also reacting with uranium and dissolve it. When exposed to air, uranium forms a uranium oxide layer, which is dark in color (this happens when uranium is in small particles).

Uranium has six isotopes ranging from U-233 to U-238. So they have 141 to 146 neutrons, but mostly common isotopes are U-238 and U-235. Uranium is known to be a radioactive metal. When it decays it emits alpha particles, and the radioactivity of uranium is very slow. So the half-life of U-238 is about 4.47 billion years, and the half-life of U-235 is about 7.4 million years. Uranium is naturally present on earth in ores, but present in very minute concentrations, and it is extracted and converted to uranium dioxide or other chemical forms, so that it can be used in the industries. Since its slowly decaying, uranium is used to determine the age of the earth. U-235 has the capability to start a nuclear chain reaction. It is fissile. So when it is bombarded with neutrons, the U-235 nuclei are divided into two smaller nuclei and release binding energy and more nuclei. Due to this chain reaction, an explosion can occur. So uranium is used in nuclear reactors, in nuclear power plants and atomic bombs.

Plutonium

The chemical symbol of plutonium is Pu. The atomic number of it is 94. Plutonium is a trans-uranic radioactive element in the actinide series. It is a solid metal with a silvery-grey appearance. The electronic configuration of plutonium is [Rn] 5f⁶ 7s², and it shows four oxidation states. Plutonium has six allotropes. At room temperature alpha form is the most common and stable allotrope of plutonium. It is hard and brittle. Though it is a metal, it is not a good heat or electricity conductor. Plutonium reacts with nonmetals like halogens, carbon, silicon, etc. When exposed to air it oxidizes rapidly, and the oxide layer is dull gray in color. Boiling point of plutonium is unusually high, which is about 3228 °C. Melting point is 639.4 °C, which is relatively low. Among the plutonium isotopes, Pu-239 is the fissile isotope. So this isotope is used in nuclear weapons and other explosives. It is also used to generate power and heat.