Mixture Of Stable And Radioactive Isotopes example essay topic

609 words
I am the chemical element known as Krypton. Ican also be referred as Kr. I will be telling you about my history, my properties, my family and my occurrence. I will also be telling you about my uses and ores, also the analytical methods based on me. I received the name krypton from the Greek word " hidden' because I was hiding for so long, undetected. I am from a rare group of gases called noble gases.

The other noble gases are helium, xenon, neon, argon and radon. I was discovered in England in 1898 almost 100 years ago by Sir William Ramsey and Morris W. Travers. They found me in the less volatile part of inert-gas mixture left after oxygen had been chemically removed from a sample of air. I am about one millionth of the earth's atmosphere. Only about 2 x 10-8% of the weight of the earth am I. I am a colorless, odorless and tasteless gas.

My atomic number is 36. My atomic weight is 83.80. My melting point is -157.20^0 C or -251.5^0 F. My gas density at 0^0 C is 3.749 g / liter. My valence is 0, 2. Many of my physical properties differ according to various scientists.

The outer shell of my atom is filled with electrons in a stable structure. That is why there is only one atom in my element. No one yet has prepared a chemical compound for me that is stable at room temperature. I can be trapped in crystals of different host compounds to form a clathrate. The radioactive isotopes of me known to this point are 76 Kr, 77 Kr, 79 Kr, 81 Kr, 83 Kr, 85 Kr, 87 Kr-95 Kr and 97 Kr. My isotopes a reproduced as by-products of nuclear fission of uranium in nuclear reactors.

They can also be formed in particle accelerator such as the cyclotron. Until 1962, I, like other members of my noble gas family, was thought to be chemically inert. Even now the only well known characteristics of my compound are, KrF 2, and its complexes. The can be prepared by passing an electric discharge through a 1: 1 mixture of gaseous fluorine and me at -188^0 C. After the reaction is complete, the reactor will be warmed and put into a glass vessel. I arise in the earth's soil, through the breakdown of uranium, but not the radioactive breakdown though. That may be why I am very similar to another noble gas, Xenon.

Also, the mixture of stable and radioactive isotopes of me are produced in nuclear reactors by the slow neutron fission of uranium. The only stable source for me is air. The content of my gases can be detected and determined by gas chromatography. Before scientists had these methods of determining my content, they obtained it by passing a gas sample through an electric discharge tube at low pressures and analyzing the light with a spectrometer. The principle and most common use for me in the world is in filling electric lamps and electronic devices of various types. Iam used to fill greenish fluorescent lights.

Both Argon and I can be used to fill lamps with light. My radioactive 85 is used in leak testing of sealed containers. Another use for me is continuous measurements, determining thickness of materials, such as paper. I hope you have learned a little bit more about such a small element like me.