Polonium Uses

Polonium is a rare kind of radioactive element found on the earth. The other name of polonium is Radium F. Chemically, it is represented with the symbol Po. In the periodic table, it is placed in group 16 which is also known as chalcogen family. Other members of this family include oxygen, sulfur, selenium, and tellurium. It is the heaviest chemical element of this group. As it is highly radioactive, most of its uses are confined to research based studies. There are rarely any commercial uses of polonium.

History
The credit for discovering polonium goes to Marie curie and her husband. They discovered it in the year 1898. The name polonium actually originated from Poland which happened to be the native land of Marie Curie. They were inspired by Henry Becquerel's discovery of radioactivity and were doing research on uranium ores to identify the cause of radioactivity. While working, they found that after separating uranium and thorium from the ores, there was another radioactive material which is more unstable than uranium and thorium and exhibit higher radioactivity. After polonium, this couple went on to discover another radioactive element radium.

Facts
Basically, polonium is rarely found in nature. This is because it is formed by radioactive disintegration or breaking down of natural form of uranium 238 which is also a radioactive element. Moreover, it has a very short half life period. Thus the only natural source of polonium is uranium ores. Even in this ore its concentration is very low. One metric ton of uranium ores contains hardly 100 micrograms of polonium.

Now, polonium can be produced artificially. Its process of manufacturing was discovered in the year 1934 when scientists bombarded naturally occurring bismuth with neutrons. Now, it is mostly prepared with the help of neutron refluxes present in nuclear reactors.

Atomic number of polonium is 84. In all, there are 33 known isotopes of polonium. In fact, polonium is well-known for its highest number of isotopes. The atomic masses of all these isotopes are in between 188 and 220 and all of them are radioactive in nature. Among them, polonium 210 is the most commonly found isotope and is most widely used for practical applications.

Element polonium is categorized as metalloid. The term metalloid is used for those chemical elements that exhibit properties of both metals as well as non metals. Polonium is a soft metal and can be identified with its silvery gray color. It has extremely high volatility. In fact, if you heat the metal at 55 degrees Celsius, half the sample would be vaporized in the first 45 hours itself. The chemical properties of polonium have lots of similarities with that of bismuth. It is highly soluble in acidic substances and only partially soluble in alkaline substances.

Uses
Polonium is one such element which is rarely found naturally. Even artificial production of polonium is barely 100 grams in a year. For all these reasons, there are restricted uses of polonium. Some of the key polonium 210 uses are given below:

• Polonium 210 is widely used as source of neutrons. It is combined with beryllium for this purpose. The alpha particle emitted by the radioactive polonium helps in release of neutrons from beryllium. However, one need to own a license to use polonium as a neutron source.
• A small amount of polonium releases a large amount of energy every second in the form of alpha particles. For this reason, it has been used in thermoelectric cells of artificial satellites.
• Those brushes that are being used for cleaning up accumulated dust particles from camera lenses and photographic films have polonium 210 in them.
• Another key application is in those devices which are used for elimination of static electricity in various machines. Such devices are needed in paper rolling machine, spinning synthetic fibers, plastic sheet manufacturing, etc.
• It is used in radioisotope thermoelectric generator. This device converts the energy released by the radioactive decay of an element into electricity. It is needed as a power source for unmanned remote facilities such as lighthouse and space probe.
• Research is going on to find out whether it can also be used as a source of heat for spacecraft. However, it may not be used in long-term space missions because of its short half-life period.

Polonium is a toxic chemical substance. It can cause severe damage to human body tissues if it is ingested or inhaled. Therefore, extra precaution is always needed while handling this chemical.